Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
* 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6: (21 commits) HWPOISON: Enable error_remove_page on btrfs HWPOISON: Add simple debugfs interface to inject hwpoison on arbitary PFNs HWPOISON: Add madvise() based injector for hardware poisoned pages v4 HWPOISON: Enable error_remove_page for NFS HWPOISON: Enable .remove_error_page for migration aware file systems HWPOISON: The high level memory error handler in the VM v7 HWPOISON: Add PR_MCE_KILL prctl to control early kill behaviour per process HWPOISON: shmem: call set_page_dirty() with locked page HWPOISON: Define a new error_remove_page address space op for async truncation HWPOISON: Add invalidate_inode_page HWPOISON: Refactor truncate to allow direct truncating of page v2 HWPOISON: check and isolate corrupted free pages v2 HWPOISON: Handle hardware poisoned pages in try_to_unmap HWPOISON: Use bitmask/action code for try_to_unmap behaviour HWPOISON: x86: Add VM_FAULT_HWPOISON handling to x86 page fault handler v2 HWPOISON: Add poison check to page fault handling HWPOISON: Add basic support for poisoned pages in fault handler v3 HWPOISON: Add new SIGBUS error codes for hardware poison signals HWPOISON: Add support for poison swap entries v2 HWPOISON: Export some rmap vma locking to outside world ...
This commit is contained in:
Linus Torvalds
commit
db16826367
@ -536,6 +536,7 @@ struct address_space_operations {
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/* migrate the contents of a page to the specified target */
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int (*migratepage) (struct page *, struct page *);
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int (*launder_page) (struct page *);
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int (*error_remove_page) (struct mapping *mapping, struct page *page);
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};
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writepage: called by the VM to write a dirty page to backing store.
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@ -694,6 +695,12 @@ struct address_space_operations {
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prevent redirtying the page, it is kept locked during the whole
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operation.
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error_remove_page: normally set to generic_error_remove_page if truncation
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is ok for this address space. Used for memory failure handling.
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Setting this implies you deal with pages going away under you,
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unless you have them locked or reference counts increased.
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The File Object
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===============
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@ -32,6 +32,8 @@ Currently, these files are in /proc/sys/vm:
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- legacy_va_layout
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- lowmem_reserve_ratio
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- max_map_count
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- memory_failure_early_kill
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- memory_failure_recovery
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- min_free_kbytes
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- min_slab_ratio
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- min_unmapped_ratio
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@ -53,7 +55,6 @@ Currently, these files are in /proc/sys/vm:
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- vfs_cache_pressure
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- zone_reclaim_mode
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==============================================================
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block_dump
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@ -275,6 +276,44 @@ e.g., up to one or two maps per allocation.
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The default value is 65536.
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=============================================================
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memory_failure_early_kill:
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Control how to kill processes when uncorrected memory error (typically
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a 2bit error in a memory module) is detected in the background by hardware
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that cannot be handled by the kernel. In some cases (like the page
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still having a valid copy on disk) the kernel will handle the failure
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transparently without affecting any applications. But if there is
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no other uptodate copy of the data it will kill to prevent any data
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corruptions from propagating.
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1: Kill all processes that have the corrupted and not reloadable page mapped
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as soon as the corruption is detected. Note this is not supported
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for a few types of pages, like kernel internally allocated data or
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the swap cache, but works for the majority of user pages.
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0: Only unmap the corrupted page from all processes and only kill a process
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who tries to access it.
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The kill is done using a catchable SIGBUS with BUS_MCEERR_AO, so processes can
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handle this if they want to.
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This is only active on architectures/platforms with advanced machine
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check handling and depends on the hardware capabilities.
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Applications can override this setting individually with the PR_MCE_KILL prctl
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==============================================================
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memory_failure_recovery
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Enable memory failure recovery (when supported by the platform)
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1: Attempt recovery.
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0: Always panic on a memory failure.
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==============================================================
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min_free_kbytes:
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@ -167,6 +167,7 @@ force_sig_info_fault(int si_signo, int si_code, unsigned long address,
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info.si_errno = 0;
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info.si_code = si_code;
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info.si_addr = (void __user *)address;
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info.si_addr_lsb = si_code == BUS_MCEERR_AR ? PAGE_SHIFT : 0;
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force_sig_info(si_signo, &info, tsk);
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}
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@ -790,10 +791,12 @@ out_of_memory(struct pt_regs *regs, unsigned long error_code,
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}
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static void
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do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address)
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do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address,
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unsigned int fault)
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{
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struct task_struct *tsk = current;
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struct mm_struct *mm = tsk->mm;
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int code = BUS_ADRERR;
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up_read(&mm->mmap_sem);
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@ -809,7 +812,15 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address)
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tsk->thread.error_code = error_code;
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tsk->thread.trap_no = 14;
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force_sig_info_fault(SIGBUS, BUS_ADRERR, address, tsk);
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#ifdef CONFIG_MEMORY_FAILURE
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if (fault & VM_FAULT_HWPOISON) {
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printk(KERN_ERR
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"MCE: Killing %s:%d due to hardware memory corruption fault at %lx\n",
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tsk->comm, tsk->pid, address);
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code = BUS_MCEERR_AR;
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}
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#endif
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force_sig_info_fault(SIGBUS, code, address, tsk);
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}
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static noinline void
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@ -819,8 +830,8 @@ mm_fault_error(struct pt_regs *regs, unsigned long error_code,
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if (fault & VM_FAULT_OOM) {
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out_of_memory(regs, error_code, address);
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} else {
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if (fault & VM_FAULT_SIGBUS)
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do_sigbus(regs, error_code, address);
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if (fault & (VM_FAULT_SIGBUS|VM_FAULT_HWPOISON))
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do_sigbus(regs, error_code, address, fault);
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else
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BUG();
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}
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@ -5269,6 +5269,7 @@ static const struct address_space_operations btrfs_aops = {
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.invalidatepage = btrfs_invalidatepage,
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.releasepage = btrfs_releasepage,
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.set_page_dirty = btrfs_set_page_dirty,
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.error_remove_page = generic_error_remove_page,
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};
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static const struct address_space_operations btrfs_symlink_aops = {
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@ -819,6 +819,7 @@ const struct address_space_operations ext2_aops = {
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.writepages = ext2_writepages,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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const struct address_space_operations ext2_aops_xip = {
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@ -837,6 +838,7 @@ const struct address_space_operations ext2_nobh_aops = {
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.direct_IO = ext2_direct_IO,
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.writepages = ext2_writepages,
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.migratepage = buffer_migrate_page,
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.error_remove_page = generic_error_remove_page,
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};
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/*
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@ -1830,6 +1830,7 @@ static const struct address_space_operations ext3_ordered_aops = {
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.direct_IO = ext3_direct_IO,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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static const struct address_space_operations ext3_writeback_aops = {
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@ -1845,6 +1846,7 @@ static const struct address_space_operations ext3_writeback_aops = {
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.direct_IO = ext3_direct_IO,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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static const struct address_space_operations ext3_journalled_aops = {
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@ -1859,6 +1861,7 @@ static const struct address_space_operations ext3_journalled_aops = {
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.invalidatepage = ext3_invalidatepage,
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.releasepage = ext3_releasepage,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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void ext3_set_aops(struct inode *inode)
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@ -3386,6 +3386,7 @@ static const struct address_space_operations ext4_ordered_aops = {
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.direct_IO = ext4_direct_IO,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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static const struct address_space_operations ext4_writeback_aops = {
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@ -3401,6 +3402,7 @@ static const struct address_space_operations ext4_writeback_aops = {
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.direct_IO = ext4_direct_IO,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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static const struct address_space_operations ext4_journalled_aops = {
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@ -3415,6 +3417,7 @@ static const struct address_space_operations ext4_journalled_aops = {
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.invalidatepage = ext4_invalidatepage,
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.releasepage = ext4_releasepage,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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static const struct address_space_operations ext4_da_aops = {
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@ -3431,6 +3434,7 @@ static const struct address_space_operations ext4_da_aops = {
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.direct_IO = ext4_direct_IO,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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void ext4_set_aops(struct inode *inode)
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@ -1135,6 +1135,7 @@ static const struct address_space_operations gfs2_writeback_aops = {
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.direct_IO = gfs2_direct_IO,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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static const struct address_space_operations gfs2_ordered_aops = {
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@ -1151,6 +1152,7 @@ static const struct address_space_operations gfs2_ordered_aops = {
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.direct_IO = gfs2_direct_IO,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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static const struct address_space_operations gfs2_jdata_aops = {
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@ -1166,6 +1168,7 @@ static const struct address_space_operations gfs2_jdata_aops = {
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.invalidatepage = gfs2_invalidatepage,
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.releasepage = gfs2_releasepage,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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void gfs2_set_aops(struct inode *inode)
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@ -525,6 +525,7 @@ const struct address_space_operations nfs_file_aops = {
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.direct_IO = nfs_direct_IO,
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.migratepage = nfs_migrate_page,
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.launder_page = nfs_launder_page,
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.error_remove_page = generic_error_remove_page,
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};
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/*
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@ -1550,6 +1550,7 @@ const struct address_space_operations ntfs_aops = {
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.migratepage = buffer_migrate_page, /* Move a page cache page from
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one physical page to an
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other. */
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.error_remove_page = generic_error_remove_page,
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};
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/**
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@ -1569,6 +1570,7 @@ const struct address_space_operations ntfs_mst_aops = {
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.migratepage = buffer_migrate_page, /* Move a page cache page from
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one physical page to an
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other. */
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.error_remove_page = generic_error_remove_page,
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};
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#ifdef NTFS_RW
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@ -2022,4 +2022,5 @@ const struct address_space_operations ocfs2_aops = {
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.releasepage = ocfs2_releasepage,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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@ -97,7 +97,11 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
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"Committed_AS: %8lu kB\n"
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"VmallocTotal: %8lu kB\n"
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"VmallocUsed: %8lu kB\n"
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"VmallocChunk: %8lu kB\n",
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"VmallocChunk: %8lu kB\n"
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#ifdef CONFIG_MEMORY_FAILURE
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"HardwareCorrupted: %8lu kB\n"
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#endif
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,
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K(i.totalram),
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K(i.freeram),
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K(i.bufferram),
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@ -144,6 +148,9 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
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(unsigned long)VMALLOC_TOTAL >> 10,
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vmi.used >> 10,
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vmi.largest_chunk >> 10
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#ifdef CONFIG_MEMORY_FAILURE
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,atomic_long_read(&mce_bad_pages) << (PAGE_SHIFT - 10)
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#endif
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);
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hugetlb_report_meminfo(m);
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@ -1635,4 +1635,5 @@ const struct address_space_operations xfs_address_space_operations = {
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.direct_IO = xfs_vm_direct_IO,
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.migratepage = buffer_migrate_page,
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.is_partially_uptodate = block_is_partially_uptodate,
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.error_remove_page = generic_error_remove_page,
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};
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@ -34,6 +34,7 @@
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#define MADV_REMOVE 9 /* remove these pages & resources */
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#define MADV_DONTFORK 10 /* don't inherit across fork */
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#define MADV_DOFORK 11 /* do inherit across fork */
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#define MADV_HWPOISON 100 /* poison a page for testing */
|
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#define MADV_MERGEABLE 12 /* KSM may merge identical pages */
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#define MADV_UNMERGEABLE 13 /* KSM may not merge identical pages */
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@ -82,6 +82,7 @@ typedef struct siginfo {
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#ifdef __ARCH_SI_TRAPNO
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int _trapno; /* TRAP # which caused the signal */
|
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#endif
|
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short _addr_lsb; /* LSB of the reported address */
|
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} _sigfault;
|
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|
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/* SIGPOLL */
|
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@ -112,6 +113,7 @@ typedef struct siginfo {
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#ifdef __ARCH_SI_TRAPNO
|
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#define si_trapno _sifields._sigfault._trapno
|
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#endif
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#define si_addr_lsb _sifields._sigfault._addr_lsb
|
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#define si_band _sifields._sigpoll._band
|
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#define si_fd _sifields._sigpoll._fd
|
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|
||||
@ -192,7 +194,11 @@ typedef struct siginfo {
|
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#define BUS_ADRALN (__SI_FAULT|1) /* invalid address alignment */
|
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#define BUS_ADRERR (__SI_FAULT|2) /* non-existant physical address */
|
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#define BUS_OBJERR (__SI_FAULT|3) /* object specific hardware error */
|
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#define NSIGBUS 3
|
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/* hardware memory error consumed on a machine check: action required */
|
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#define BUS_MCEERR_AR (__SI_FAULT|4)
|
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/* hardware memory error detected in process but not consumed: action optional*/
|
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#define BUS_MCEERR_AO (__SI_FAULT|5)
|
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#define NSIGBUS 5
|
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|
||||
/*
|
||||
* SIGTRAP si_codes
|
||||
|
||||
@ -595,6 +595,7 @@ struct address_space_operations {
|
||||
int (*launder_page) (struct page *);
|
||||
int (*is_partially_uptodate) (struct page *, read_descriptor_t *,
|
||||
unsigned long);
|
||||
int (*error_remove_page)(struct address_space *, struct page *);
|
||||
};
|
||||
|
||||
/*
|
||||
|
||||
@ -695,11 +695,12 @@ static inline int page_mapped(struct page *page)
|
||||
#define VM_FAULT_SIGBUS 0x0002
|
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#define VM_FAULT_MAJOR 0x0004
|
||||
#define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */
|
||||
#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned page */
|
||||
|
||||
#define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */
|
||||
#define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */
|
||||
|
||||
#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS)
|
||||
#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_HWPOISON)
|
||||
|
||||
/*
|
||||
* Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
|
||||
@ -794,6 +795,11 @@ static inline void unmap_shared_mapping_range(struct address_space *mapping,
|
||||
extern int vmtruncate(struct inode * inode, loff_t offset);
|
||||
extern int vmtruncate_range(struct inode * inode, loff_t offset, loff_t end);
|
||||
|
||||
int truncate_inode_page(struct address_space *mapping, struct page *page);
|
||||
int generic_error_remove_page(struct address_space *mapping, struct page *page);
|
||||
|
||||
int invalidate_inode_page(struct page *page);
|
||||
|
||||
#ifdef CONFIG_MMU
|
||||
extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
|
||||
unsigned long address, unsigned int flags);
|
||||
@ -1308,5 +1314,12 @@ void vmemmap_populate_print_last(void);
|
||||
extern int account_locked_memory(struct mm_struct *mm, struct rlimit *rlim,
|
||||
size_t size);
|
||||
extern void refund_locked_memory(struct mm_struct *mm, size_t size);
|
||||
|
||||
extern void memory_failure(unsigned long pfn, int trapno);
|
||||
extern int __memory_failure(unsigned long pfn, int trapno, int ref);
|
||||
extern int sysctl_memory_failure_early_kill;
|
||||
extern int sysctl_memory_failure_recovery;
|
||||
extern atomic_long_t mce_bad_pages;
|
||||
|
||||
#endif /* __KERNEL__ */
|
||||
#endif /* _LINUX_MM_H */
|
||||
|
||||
@ -51,6 +51,9 @@
|
||||
* PG_buddy is set to indicate that the page is free and in the buddy system
|
||||
* (see mm/page_alloc.c).
|
||||
*
|
||||
* PG_hwpoison indicates that a page got corrupted in hardware and contains
|
||||
* data with incorrect ECC bits that triggered a machine check. Accessing is
|
||||
* not safe since it may cause another machine check. Don't touch!
|
||||
*/
|
||||
|
||||
/*
|
||||
@ -101,6 +104,9 @@ enum pageflags {
|
||||
#endif
|
||||
#ifdef CONFIG_ARCH_USES_PG_UNCACHED
|
||||
PG_uncached, /* Page has been mapped as uncached */
|
||||
#endif
|
||||
#ifdef CONFIG_MEMORY_FAILURE
|
||||
PG_hwpoison, /* hardware poisoned page. Don't touch */
|
||||
#endif
|
||||
__NR_PAGEFLAGS,
|
||||
|
||||
@ -269,6 +275,15 @@ PAGEFLAG(Uncached, uncached)
|
||||
PAGEFLAG_FALSE(Uncached)
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_MEMORY_FAILURE
|
||||
PAGEFLAG(HWPoison, hwpoison)
|
||||
TESTSETFLAG(HWPoison, hwpoison)
|
||||
#define __PG_HWPOISON (1UL << PG_hwpoison)
|
||||
#else
|
||||
PAGEFLAG_FALSE(HWPoison)
|
||||
#define __PG_HWPOISON 0
|
||||
#endif
|
||||
|
||||
static inline int PageUptodate(struct page *page)
|
||||
{
|
||||
int ret = test_bit(PG_uptodate, &(page)->flags);
|
||||
@ -393,7 +408,7 @@ static inline void __ClearPageTail(struct page *page)
|
||||
1 << PG_private | 1 << PG_private_2 | \
|
||||
1 << PG_buddy | 1 << PG_writeback | 1 << PG_reserved | \
|
||||
1 << PG_slab | 1 << PG_swapcache | 1 << PG_active | \
|
||||
1 << PG_unevictable | __PG_MLOCKED)
|
||||
1 << PG_unevictable | __PG_MLOCKED | __PG_HWPOISON)
|
||||
|
||||
/*
|
||||
* Flags checked when a page is prepped for return by the page allocator.
|
||||
|
||||
@ -88,4 +88,6 @@
|
||||
#define PR_TASK_PERF_EVENTS_DISABLE 31
|
||||
#define PR_TASK_PERF_EVENTS_ENABLE 32
|
||||
|
||||
#define PR_MCE_KILL 33
|
||||
|
||||
#endif /* _LINUX_PRCTL_H */
|
||||
|
||||
@ -81,7 +81,19 @@ static inline void page_dup_rmap(struct page *page)
|
||||
*/
|
||||
int page_referenced(struct page *, int is_locked,
|
||||
struct mem_cgroup *cnt, unsigned long *vm_flags);
|
||||
int try_to_unmap(struct page *, int ignore_refs);
|
||||
enum ttu_flags {
|
||||
TTU_UNMAP = 0, /* unmap mode */
|
||||
TTU_MIGRATION = 1, /* migration mode */
|
||||
TTU_MUNLOCK = 2, /* munlock mode */
|
||||
TTU_ACTION_MASK = 0xff,
|
||||
|
||||
TTU_IGNORE_MLOCK = (1 << 8), /* ignore mlock */
|
||||
TTU_IGNORE_ACCESS = (1 << 9), /* don't age */
|
||||
TTU_IGNORE_HWPOISON = (1 << 10),/* corrupted page is recoverable */
|
||||
};
|
||||
#define TTU_ACTION(x) ((x) & TTU_ACTION_MASK)
|
||||
|
||||
int try_to_unmap(struct page *, enum ttu_flags flags);
|
||||
|
||||
/*
|
||||
* Called from mm/filemap_xip.c to unmap empty zero page
|
||||
@ -108,6 +120,13 @@ int page_mkclean(struct page *);
|
||||
*/
|
||||
int try_to_munlock(struct page *);
|
||||
|
||||
/*
|
||||
* Called by memory-failure.c to kill processes.
|
||||
*/
|
||||
struct anon_vma *page_lock_anon_vma(struct page *page);
|
||||
void page_unlock_anon_vma(struct anon_vma *anon_vma);
|
||||
int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma);
|
||||
|
||||
#else /* !CONFIG_MMU */
|
||||
|
||||
#define anon_vma_init() do {} while (0)
|
||||
|
||||
@ -1734,6 +1734,7 @@ extern cputime_t task_gtime(struct task_struct *p);
|
||||
#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
|
||||
#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
|
||||
#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
|
||||
#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */
|
||||
#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
|
||||
#define PF_DUMPCORE 0x00000200 /* dumped core */
|
||||
#define PF_SIGNALED 0x00000400 /* killed by a signal */
|
||||
@ -1753,6 +1754,7 @@ extern cputime_t task_gtime(struct task_struct *p);
|
||||
#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
|
||||
#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
|
||||
#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */
|
||||
#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
|
||||
#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
|
||||
#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
|
||||
#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezeable */
|
||||
|
||||
@ -34,15 +34,37 @@ static inline int current_is_kswapd(void)
|
||||
* the type/offset into the pte as 5/27 as well.
|
||||
*/
|
||||
#define MAX_SWAPFILES_SHIFT 5
|
||||
#ifndef CONFIG_MIGRATION
|
||||
#define MAX_SWAPFILES (1 << MAX_SWAPFILES_SHIFT)
|
||||
|
||||
/*
|
||||
* Use some of the swap files numbers for other purposes. This
|
||||
* is a convenient way to hook into the VM to trigger special
|
||||
* actions on faults.
|
||||
*/
|
||||
|
||||
/*
|
||||
* NUMA node memory migration support
|
||||
*/
|
||||
#ifdef CONFIG_MIGRATION
|
||||
#define SWP_MIGRATION_NUM 2
|
||||
#define SWP_MIGRATION_READ (MAX_SWAPFILES + SWP_HWPOISON_NUM)
|
||||
#define SWP_MIGRATION_WRITE (MAX_SWAPFILES + SWP_HWPOISON_NUM + 1)
|
||||
#else
|
||||
/* Use last two entries for page migration swap entries */
|
||||
#define MAX_SWAPFILES ((1 << MAX_SWAPFILES_SHIFT)-2)
|
||||
#define SWP_MIGRATION_READ MAX_SWAPFILES
|
||||
#define SWP_MIGRATION_WRITE (MAX_SWAPFILES + 1)
|
||||
#define SWP_MIGRATION_NUM 0
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Handling of hardware poisoned pages with memory corruption.
|
||||
*/
|
||||
#ifdef CONFIG_MEMORY_FAILURE
|
||||
#define SWP_HWPOISON_NUM 1
|
||||
#define SWP_HWPOISON MAX_SWAPFILES
|
||||
#else
|
||||
#define SWP_HWPOISON_NUM 0
|
||||
#endif
|
||||
|
||||
#define MAX_SWAPFILES \
|
||||
((1 << MAX_SWAPFILES_SHIFT) - SWP_MIGRATION_NUM - SWP_HWPOISON_NUM)
|
||||
|
||||
/*
|
||||
* Magic header for a swap area. The first part of the union is
|
||||
* what the swap magic looks like for the old (limited to 128MB)
|
||||
|
||||
@ -131,3 +131,41 @@ static inline int is_write_migration_entry(swp_entry_t entry)
|
||||
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_MEMORY_FAILURE
|
||||
/*
|
||||
* Support for hardware poisoned pages
|
||||
*/
|
||||
static inline swp_entry_t make_hwpoison_entry(struct page *page)
|
||||
{
|
||||
BUG_ON(!PageLocked(page));
|
||||
return swp_entry(SWP_HWPOISON, page_to_pfn(page));
|
||||
}
|
||||
|
||||
static inline int is_hwpoison_entry(swp_entry_t entry)
|
||||
{
|
||||
return swp_type(entry) == SWP_HWPOISON;
|
||||
}
|
||||
#else
|
||||
|
||||
static inline swp_entry_t make_hwpoison_entry(struct page *page)
|
||||
{
|
||||
return swp_entry(0, 0);
|
||||
}
|
||||
|
||||
static inline int is_hwpoison_entry(swp_entry_t swp)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
#endif
|
||||
|
||||
#if defined(CONFIG_MEMORY_FAILURE) || defined(CONFIG_MIGRATION)
|
||||
static inline int non_swap_entry(swp_entry_t entry)
|
||||
{
|
||||
return swp_type(entry) >= MAX_SWAPFILES;
|
||||
}
|
||||
#else
|
||||
static inline int non_swap_entry(swp_entry_t entry)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
#endif
|
||||
|
||||
22
kernel/sys.c
22
kernel/sys.c
@ -1542,6 +1542,28 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
|
||||
current->timer_slack_ns = arg2;
|
||||
error = 0;
|
||||
break;
|
||||
case PR_MCE_KILL:
|
||||
if (arg4 | arg5)
|
||||
return -EINVAL;
|
||||
switch (arg2) {
|
||||
case 0:
|
||||
if (arg3 != 0)
|
||||
return -EINVAL;
|
||||
current->flags &= ~PF_MCE_PROCESS;
|
||||
break;
|
||||
case 1:
|
||||
current->flags |= PF_MCE_PROCESS;
|
||||
if (arg3 != 0)
|
||||
current->flags |= PF_MCE_EARLY;
|
||||
else
|
||||
current->flags &= ~PF_MCE_EARLY;
|
||||
break;
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
error = 0;
|
||||
break;
|
||||
|
||||
default:
|
||||
error = -EINVAL;
|
||||
break;
|
||||
|
||||
@ -1398,6 +1398,31 @@ static struct ctl_table vm_table[] = {
|
||||
.mode = 0644,
|
||||
.proc_handler = &scan_unevictable_handler,
|
||||
},
|
||||
#ifdef CONFIG_MEMORY_FAILURE
|
||||
{
|
||||
.ctl_name = CTL_UNNUMBERED,
|
||||
.procname = "memory_failure_early_kill",
|
||||
.data = &sysctl_memory_failure_early_kill,
|
||||
.maxlen = sizeof(sysctl_memory_failure_early_kill),
|
||||
.mode = 0644,
|
||||
.proc_handler = &proc_dointvec_minmax,
|
||||
.strategy = &sysctl_intvec,
|
||||
.extra1 = &zero,
|
||||
.extra2 = &one,
|
||||
},
|
||||
{
|
||||
.ctl_name = CTL_UNNUMBERED,
|
||||
.procname = "memory_failure_recovery",
|
||||
.data = &sysctl_memory_failure_recovery,
|
||||
.maxlen = sizeof(sysctl_memory_failure_recovery),
|
||||
.mode = 0644,
|
||||
.proc_handler = &proc_dointvec_minmax,
|
||||
.strategy = &sysctl_intvec,
|
||||
.extra1 = &zero,
|
||||
.extra2 = &one,
|
||||
},
|
||||
#endif
|
||||
|
||||
/*
|
||||
* NOTE: do not add new entries to this table unless you have read
|
||||
* Documentation/sysctl/ctl_unnumbered.txt
|
||||
|
||||
14
mm/Kconfig
14
mm/Kconfig
@ -245,6 +245,20 @@ config DEFAULT_MMAP_MIN_ADDR
|
||||
/proc/sys/vm/mmap_min_addr tunable.
|
||||
|
||||
|
||||
config MEMORY_FAILURE
|
||||
depends on MMU
|
||||
depends on X86_MCE
|
||||
bool "Enable recovery from hardware memory errors"
|
||||
help
|
||||
Enables code to recover from some memory failures on systems
|
||||
with MCA recovery. This allows a system to continue running
|
||||
even when some of its memory has uncorrected errors. This requires
|
||||
special hardware support and typically ECC memory.
|
||||
|
||||
config HWPOISON_INJECT
|
||||
tristate "Poison pages injector"
|
||||
depends on MEMORY_FAILURE && DEBUG_KERNEL
|
||||
|
||||
config NOMMU_INITIAL_TRIM_EXCESS
|
||||
int "Turn on mmap() excess space trimming before booting"
|
||||
depends on !MMU
|
||||
|
||||
@ -41,5 +41,7 @@ obj-$(CONFIG_SMP) += allocpercpu.o
|
||||
endif
|
||||
obj-$(CONFIG_QUICKLIST) += quicklist.o
|
||||
obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o page_cgroup.o
|
||||
obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o
|
||||
obj-$(CONFIG_HWPOISON_INJECT) += hwpoison-inject.o
|
||||
obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o
|
||||
obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o
|
||||
|
||||
@ -104,6 +104,10 @@
|
||||
*
|
||||
* ->task->proc_lock
|
||||
* ->dcache_lock (proc_pid_lookup)
|
||||
*
|
||||
* (code doesn't rely on that order, so you could switch it around)
|
||||
* ->tasklist_lock (memory_failure, collect_procs_ao)
|
||||
* ->i_mmap_lock
|
||||
*/
|
||||
|
||||
/*
|
||||
|
||||
41
mm/hwpoison-inject.c
Normal file
41
mm/hwpoison-inject.c
Normal file
@ -0,0 +1,41 @@
|
||||
/* Inject a hwpoison memory failure on a arbitary pfn */
|
||||
#include <linux/module.h>
|
||||
#include <linux/debugfs.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/mm.h>
|
||||
|
||||
static struct dentry *hwpoison_dir, *corrupt_pfn;
|
||||
|
||||
static int hwpoison_inject(void *data, u64 val)
|
||||
{
|
||||
if (!capable(CAP_SYS_ADMIN))
|
||||
return -EPERM;
|
||||
printk(KERN_INFO "Injecting memory failure at pfn %Lx\n", val);
|
||||
return __memory_failure(val, 18, 0);
|
||||
}
|
||||
|
||||
DEFINE_SIMPLE_ATTRIBUTE(hwpoison_fops, NULL, hwpoison_inject, "%lli\n");
|
||||
|
||||
static void pfn_inject_exit(void)
|
||||
{
|
||||
if (hwpoison_dir)
|
||||
debugfs_remove_recursive(hwpoison_dir);
|
||||
}
|
||||
|
||||
static int pfn_inject_init(void)
|
||||
{
|
||||
hwpoison_dir = debugfs_create_dir("hwpoison", NULL);
|
||||
if (hwpoison_dir == NULL)
|
||||
return -ENOMEM;
|
||||
corrupt_pfn = debugfs_create_file("corrupt-pfn", 0600, hwpoison_dir,
|
||||
NULL, &hwpoison_fops);
|
||||
if (corrupt_pfn == NULL) {
|
||||
pfn_inject_exit();
|
||||
return -ENOMEM;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
module_init(pfn_inject_init);
|
||||
module_exit(pfn_inject_exit);
|
||||
MODULE_LICENSE("GPL");
|
||||
30
mm/madvise.c
30
mm/madvise.c
@ -218,6 +218,32 @@ static long madvise_remove(struct vm_area_struct *vma,
|
||||
return error;
|
||||
}
|
||||
|
||||
#ifdef CONFIG_MEMORY_FAILURE
|
||||
/*
|
||||
* Error injection support for memory error handling.
|
||||
*/
|
||||
static int madvise_hwpoison(unsigned long start, unsigned long end)
|
||||
{
|
||||
int ret = 0;
|
||||
|
||||
if (!capable(CAP_SYS_ADMIN))
|
||||
return -EPERM;
|
||||
for (; start < end; start += PAGE_SIZE) {
|
||||
struct page *p;
|
||||
int ret = get_user_pages(current, current->mm, start, 1,
|
||||
0, 0, &p, NULL);
|
||||
if (ret != 1)
|
||||
return ret;
|
||||
printk(KERN_INFO "Injecting memory failure for page %lx at %lx\n",
|
||||
page_to_pfn(p), start);
|
||||
/* Ignore return value for now */
|
||||
__memory_failure(page_to_pfn(p), 0, 1);
|
||||
put_page(p);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
#endif
|
||||
|
||||
static long
|
||||
madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
|
||||
unsigned long start, unsigned long end, int behavior)
|
||||
@ -308,6 +334,10 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
|
||||
int write;
|
||||
size_t len;
|
||||
|
||||
#ifdef CONFIG_MEMORY_FAILURE
|
||||
if (behavior == MADV_HWPOISON)
|
||||
return madvise_hwpoison(start, start+len_in);
|
||||
#endif
|
||||
if (!madvise_behavior_valid(behavior))
|
||||
return error;
|
||||
|
||||
|
||||
832
mm/memory-failure.c
Normal file
832
mm/memory-failure.c
Normal file
@ -0,0 +1,832 @@
|
||||
/*
|
||||
* Copyright (C) 2008, 2009 Intel Corporation
|
||||
* Authors: Andi Kleen, Fengguang Wu
|
||||
*
|
||||
* This software may be redistributed and/or modified under the terms of
|
||||
* the GNU General Public License ("GPL") version 2 only as published by the
|
||||
* Free Software Foundation.
|
||||
*
|
||||
* High level machine check handler. Handles pages reported by the
|
||||
* hardware as being corrupted usually due to a 2bit ECC memory or cache
|
||||
* failure.
|
||||
*
|
||||
* Handles page cache pages in various states. The tricky part
|
||||
* here is that we can access any page asynchronous to other VM
|
||||
* users, because memory failures could happen anytime and anywhere,
|
||||
* possibly violating some of their assumptions. This is why this code
|
||||
* has to be extremely careful. Generally it tries to use normal locking
|
||||
* rules, as in get the standard locks, even if that means the
|
||||
* error handling takes potentially a long time.
|
||||
*
|
||||
* The operation to map back from RMAP chains to processes has to walk
|
||||
* the complete process list and has non linear complexity with the number
|
||||
* mappings. In short it can be quite slow. But since memory corruptions
|
||||
* are rare we hope to get away with this.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Notebook:
|
||||
* - hugetlb needs more code
|
||||
* - kcore/oldmem/vmcore/mem/kmem check for hwpoison pages
|
||||
* - pass bad pages to kdump next kernel
|
||||
*/
|
||||
#define DEBUG 1 /* remove me in 2.6.34 */
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/mm.h>
|
||||
#include <linux/page-flags.h>
|
||||
#include <linux/sched.h>
|
||||
#include <linux/rmap.h>
|
||||
#include <linux/pagemap.h>
|
||||
#include <linux/swap.h>
|
||||
#include <linux/backing-dev.h>
|
||||
#include "internal.h"
|
||||
|
||||
int sysctl_memory_failure_early_kill __read_mostly = 0;
|
||||
|
||||
int sysctl_memory_failure_recovery __read_mostly = 1;
|
||||
|
||||
atomic_long_t mce_bad_pages __read_mostly = ATOMIC_LONG_INIT(0);
|
||||
|
||||
/*
|
||||
* Send all the processes who have the page mapped an ``action optional''
|
||||
* signal.
|
||||
*/
|
||||
static int kill_proc_ao(struct task_struct *t, unsigned long addr, int trapno,
|
||||
unsigned long pfn)
|
||||
{
|
||||
struct siginfo si;
|
||||
int ret;
|
||||
|
||||
printk(KERN_ERR
|
||||
"MCE %#lx: Killing %s:%d early due to hardware memory corruption\n",
|
||||
pfn, t->comm, t->pid);
|
||||
si.si_signo = SIGBUS;
|
||||
si.si_errno = 0;
|
||||
si.si_code = BUS_MCEERR_AO;
|
||||
si.si_addr = (void *)addr;
|
||||
#ifdef __ARCH_SI_TRAPNO
|
||||
si.si_trapno = trapno;
|
||||
#endif
|
||||
si.si_addr_lsb = PAGE_SHIFT;
|
||||
/*
|
||||
* Don't use force here, it's convenient if the signal
|
||||
* can be temporarily blocked.
|
||||
* This could cause a loop when the user sets SIGBUS
|
||||
* to SIG_IGN, but hopefully noone will do that?
|
||||
*/
|
||||
ret = send_sig_info(SIGBUS, &si, t); /* synchronous? */
|
||||
if (ret < 0)
|
||||
printk(KERN_INFO "MCE: Error sending signal to %s:%d: %d\n",
|
||||
t->comm, t->pid, ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Kill all processes that have a poisoned page mapped and then isolate
|
||||
* the page.
|
||||
*
|
||||
* General strategy:
|
||||
* Find all processes having the page mapped and kill them.
|
||||
* But we keep a page reference around so that the page is not
|
||||
* actually freed yet.
|
||||
* Then stash the page away
|
||||
*
|
||||
* There's no convenient way to get back to mapped processes
|
||||
* from the VMAs. So do a brute-force search over all
|
||||
* running processes.
|
||||
*
|
||||
* Remember that machine checks are not common (or rather
|
||||
* if they are common you have other problems), so this shouldn't
|
||||
* be a performance issue.
|
||||
*
|
||||
* Also there are some races possible while we get from the
|
||||
* error detection to actually handle it.
|
||||
*/
|
||||
|
||||
struct to_kill {
|
||||
struct list_head nd;
|
||||
struct task_struct *tsk;
|
||||
unsigned long addr;
|
||||
unsigned addr_valid:1;
|
||||
};
|
||||
|
||||
/*
|
||||
* Failure handling: if we can't find or can't kill a process there's
|
||||
* not much we can do. We just print a message and ignore otherwise.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Schedule a process for later kill.
|
||||
* Uses GFP_ATOMIC allocations to avoid potential recursions in the VM.
|
||||
* TBD would GFP_NOIO be enough?
|
||||
*/
|
||||
static void add_to_kill(struct task_struct *tsk, struct page *p,
|
||||
struct vm_area_struct *vma,
|
||||
struct list_head *to_kill,
|
||||
struct to_kill **tkc)
|
||||
{
|
||||
struct to_kill *tk;
|
||||
|
||||
if (*tkc) {
|
||||
tk = *tkc;
|
||||
*tkc = NULL;
|
||||
} else {
|
||||
tk = kmalloc(sizeof(struct to_kill), GFP_ATOMIC);
|
||||
if (!tk) {
|
||||
printk(KERN_ERR
|
||||
"MCE: Out of memory while machine check handling\n");
|
||||
return;
|
||||
}
|
||||
}
|
||||
tk->addr = page_address_in_vma(p, vma);
|
||||
tk->addr_valid = 1;
|
||||
|
||||
/*
|
||||
* In theory we don't have to kill when the page was
|
||||
* munmaped. But it could be also a mremap. Since that's
|
||||
* likely very rare kill anyways just out of paranoia, but use
|
||||
* a SIGKILL because the error is not contained anymore.
|
||||
*/
|
||||
if (tk->addr == -EFAULT) {
|
||||
pr_debug("MCE: Unable to find user space address %lx in %s\n",
|
||||
page_to_pfn(p), tsk->comm);
|
||||
tk->addr_valid = 0;
|
||||
}
|
||||
get_task_struct(tsk);
|
||||
tk->tsk = tsk;
|
||||
list_add_tail(&tk->nd, to_kill);
|
||||
}
|
||||
|
||||
/*
|
||||
* Kill the processes that have been collected earlier.
|
||||
*
|
||||
* Only do anything when DOIT is set, otherwise just free the list
|
||||
* (this is used for clean pages which do not need killing)
|
||||
* Also when FAIL is set do a force kill because something went
|
||||
* wrong earlier.
|
||||
*/
|
||||
static void kill_procs_ao(struct list_head *to_kill, int doit, int trapno,
|
||||
int fail, unsigned long pfn)
|
||||
{
|
||||
struct to_kill *tk, *next;
|
||||
|
||||
list_for_each_entry_safe (tk, next, to_kill, nd) {
|
||||
if (doit) {
|
||||
/*
|
||||
* In case something went wrong with munmaping
|
||||
* make sure the process doesn't catch the
|
||||
* signal and then access the memory. Just kill it.
|
||||
* the signal handlers
|
||||
*/
|
||||
if (fail || tk->addr_valid == 0) {
|
||||
printk(KERN_ERR
|
||||
"MCE %#lx: forcibly killing %s:%d because of failure to unmap corrupted page\n",
|
||||
pfn, tk->tsk->comm, tk->tsk->pid);
|
||||
force_sig(SIGKILL, tk->tsk);
|
||||
}
|
||||
|
||||
/*
|
||||
* In theory the process could have mapped
|
||||
* something else on the address in-between. We could
|
||||
* check for that, but we need to tell the
|
||||
* process anyways.
|
||||
*/
|
||||
else if (kill_proc_ao(tk->tsk, tk->addr, trapno,
|
||||
pfn) < 0)
|
||||
printk(KERN_ERR
|
||||
"MCE %#lx: Cannot send advisory machine check signal to %s:%d\n",
|
||||
pfn, tk->tsk->comm, tk->tsk->pid);
|
||||
}
|
||||
put_task_struct(tk->tsk);
|
||||
kfree(tk);
|
||||
}
|
||||
}
|
||||
|
||||
static int task_early_kill(struct task_struct *tsk)
|
||||
{
|
||||
if (!tsk->mm)
|
||||
return 0;
|
||||
if (tsk->flags & PF_MCE_PROCESS)
|
||||
return !!(tsk->flags & PF_MCE_EARLY);
|
||||
return sysctl_memory_failure_early_kill;
|
||||
}
|
||||
|
||||
/*
|
||||
* Collect processes when the error hit an anonymous page.
|
||||
*/
|
||||
static void collect_procs_anon(struct page *page, struct list_head *to_kill,
|
||||
struct to_kill **tkc)
|
||||
{
|
||||
struct vm_area_struct *vma;
|
||||
struct task_struct *tsk;
|
||||
struct anon_vma *av;
|
||||
|
||||
read_lock(&tasklist_lock);
|
||||
av = page_lock_anon_vma(page);
|
||||
if (av == NULL) /* Not actually mapped anymore */
|
||||
goto out;
|
||||
for_each_process (tsk) {
|
||||
if (!task_early_kill(tsk))
|
||||
continue;
|
||||
list_for_each_entry (vma, &av->head, anon_vma_node) {
|
||||
if (!page_mapped_in_vma(page, vma))
|
||||
continue;
|
||||
if (vma->vm_mm == tsk->mm)
|
||||
add_to_kill(tsk, page, vma, to_kill, tkc);
|
||||
}
|
||||
}
|
||||
page_unlock_anon_vma(av);
|
||||
out:
|
||||
read_unlock(&tasklist_lock);
|
||||
}
|
||||
|
||||
/*
|
||||
* Collect processes when the error hit a file mapped page.
|
||||
*/
|
||||
static void collect_procs_file(struct page *page, struct list_head *to_kill,
|
||||
struct to_kill **tkc)
|
||||
{
|
||||
struct vm_area_struct *vma;
|
||||
struct task_struct *tsk;
|
||||
struct prio_tree_iter iter;
|
||||
struct address_space *mapping = page->mapping;
|
||||
|
||||
/*
|
||||
* A note on the locking order between the two locks.
|
||||
* We don't rely on this particular order.
|
||||
* If you have some other code that needs a different order
|
||||
* feel free to switch them around. Or add a reverse link
|
||||
* from mm_struct to task_struct, then this could be all
|
||||
* done without taking tasklist_lock and looping over all tasks.
|
||||
*/
|
||||
|
||||
read_lock(&tasklist_lock);
|
||||
spin_lock(&mapping->i_mmap_lock);
|
||||
for_each_process(tsk) {
|
||||
pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
|
||||
|
||||
if (!task_early_kill(tsk))
|
||||
continue;
|
||||
|
||||
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff,
|
||||
pgoff) {
|
||||
/*
|
||||
* Send early kill signal to tasks where a vma covers
|
||||
* the page but the corrupted page is not necessarily
|
||||
* mapped it in its pte.
|
||||
* Assume applications who requested early kill want
|
||||
* to be informed of all such data corruptions.
|
||||
*/
|
||||
if (vma->vm_mm == tsk->mm)
|
||||
add_to_kill(tsk, page, vma, to_kill, tkc);
|
||||
}
|
||||
}
|
||||
spin_unlock(&mapping->i_mmap_lock);
|
||||
read_unlock(&tasklist_lock);
|
||||
}
|
||||
|
||||
/*
|
||||
* Collect the processes who have the corrupted page mapped to kill.
|
||||
* This is done in two steps for locking reasons.
|
||||
* First preallocate one tokill structure outside the spin locks,
|
||||
* so that we can kill at least one process reasonably reliable.
|
||||
*/
|
||||
static void collect_procs(struct page *page, struct list_head *tokill)
|
||||
{
|
||||
struct to_kill *tk;
|
||||
|
||||
if (!page->mapping)
|
||||
return;
|
||||
|
||||
tk = kmalloc(sizeof(struct to_kill), GFP_NOIO);
|
||||
if (!tk)
|
||||
return;
|
||||
if (PageAnon(page))
|
||||
collect_procs_anon(page, tokill, &tk);
|
||||
else
|
||||
collect_procs_file(page, tokill, &tk);
|
||||
kfree(tk);
|
||||
}
|
||||
|
||||
/*
|
||||
* Error handlers for various types of pages.
|
||||
*/
|
||||
|
||||
enum outcome {
|
||||
FAILED, /* Error handling failed */
|
||||
DELAYED, /* Will be handled later */
|
||||
IGNORED, /* Error safely ignored */
|
||||
RECOVERED, /* Successfully recovered */
|
||||
};
|
||||
|
||||
static const char *action_name[] = {
|
||||
[FAILED] = "Failed",
|
||||
[DELAYED] = "Delayed",
|
||||
[IGNORED] = "Ignored",
|
||||
[RECOVERED] = "Recovered",
|
||||
};
|
||||
|
||||
/*
|
||||
* Error hit kernel page.
|
||||
* Do nothing, try to be lucky and not touch this instead. For a few cases we
|
||||
* could be more sophisticated.
|
||||
*/
|
||||
static int me_kernel(struct page *p, unsigned long pfn)
|
||||
{
|
||||
return DELAYED;
|
||||
}
|
||||
|
||||
/*
|
||||
* Already poisoned page.
|
||||
*/
|
||||
static int me_ignore(struct page *p, unsigned long pfn)
|
||||
{
|
||||
return IGNORED;
|
||||
}
|
||||
|
||||
/*
|
||||
* Page in unknown state. Do nothing.
|
||||
*/
|
||||
static int me_unknown(struct page *p, unsigned long pfn)
|
||||
{
|
||||
printk(KERN_ERR "MCE %#lx: Unknown page state\n", pfn);
|
||||
return FAILED;
|
||||
}
|
||||
|
||||
/*
|
||||
* Free memory
|
||||
*/
|
||||
static int me_free(struct page *p, unsigned long pfn)
|
||||
{
|
||||
return DELAYED;
|
||||
}
|
||||
|
||||
/*
|
||||
* Clean (or cleaned) page cache page.
|
||||
*/
|
||||
static int me_pagecache_clean(struct page *p, unsigned long pfn)
|
||||
{
|
||||
int err;
|
||||
int ret = FAILED;
|
||||
struct address_space *mapping;
|
||||
|
||||
if (!isolate_lru_page(p))
|
||||
page_cache_release(p);
|
||||
|
||||
/*
|
||||
* For anonymous pages we're done the only reference left
|
||||
* should be the one m_f() holds.
|
||||
*/
|
||||
if (PageAnon(p))
|
||||
return RECOVERED;
|
||||
|
||||
/*
|
||||
* Now truncate the page in the page cache. This is really
|
||||
* more like a "temporary hole punch"
|
||||
* Don't do this for block devices when someone else
|
||||
* has a reference, because it could be file system metadata
|
||||
* and that's not safe to truncate.
|
||||
*/
|
||||
mapping = page_mapping(p);
|
||||
if (!mapping) {
|
||||
/*
|
||||
* Page has been teared down in the meanwhile
|
||||
*/
|
||||
return FAILED;
|
||||
}
|
||||
|
||||
/*
|
||||
* Truncation is a bit tricky. Enable it per file system for now.
|
||||
*
|
||||
* Open: to take i_mutex or not for this? Right now we don't.
|
||||
*/
|
||||
if (mapping->a_ops->error_remove_page) {
|
||||
err = mapping->a_ops->error_remove_page(mapping, p);
|
||||
if (err != 0) {
|
||||
printk(KERN_INFO "MCE %#lx: Failed to punch page: %d\n",
|
||||
pfn, err);
|
||||
} else if (page_has_private(p) &&
|
||||
!try_to_release_page(p, GFP_NOIO)) {
|
||||
pr_debug("MCE %#lx: failed to release buffers\n", pfn);
|
||||
} else {
|
||||
ret = RECOVERED;
|
||||
}
|
||||
} else {
|
||||
/*
|
||||
* If the file system doesn't support it just invalidate
|
||||
* This fails on dirty or anything with private pages
|
||||
*/
|
||||
if (invalidate_inode_page(p))
|
||||
ret = RECOVERED;
|
||||
else
|
||||
printk(KERN_INFO "MCE %#lx: Failed to invalidate\n",
|
||||
pfn);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Dirty cache page page
|
||||
* Issues: when the error hit a hole page the error is not properly
|
||||
* propagated.
|
||||
*/
|
||||
static int me_pagecache_dirty(struct page *p, unsigned long pfn)
|
||||
{
|
||||
struct address_space *mapping = page_mapping(p);
|
||||
|
||||
SetPageError(p);
|
||||
/* TBD: print more information about the file. */
|
||||
if (mapping) {
|
||||
/*
|
||||
* IO error will be reported by write(), fsync(), etc.
|
||||
* who check the mapping.
|
||||
* This way the application knows that something went
|
||||
* wrong with its dirty file data.
|
||||
*
|
||||
* There's one open issue:
|
||||
*
|
||||
* The EIO will be only reported on the next IO
|
||||
* operation and then cleared through the IO map.
|
||||
* Normally Linux has two mechanisms to pass IO error
|
||||
* first through the AS_EIO flag in the address space
|
||||
* and then through the PageError flag in the page.
|
||||
* Since we drop pages on memory failure handling the
|
||||
* only mechanism open to use is through AS_AIO.
|
||||
*
|
||||
* This has the disadvantage that it gets cleared on
|
||||
* the first operation that returns an error, while
|
||||
* the PageError bit is more sticky and only cleared
|
||||
* when the page is reread or dropped. If an
|
||||
* application assumes it will always get error on
|
||||
* fsync, but does other operations on the fd before
|
||||
* and the page is dropped inbetween then the error
|
||||
* will not be properly reported.
|
||||
*
|
||||
* This can already happen even without hwpoisoned
|
||||
* pages: first on metadata IO errors (which only
|
||||
* report through AS_EIO) or when the page is dropped
|
||||
* at the wrong time.
|
||||
*
|
||||
* So right now we assume that the application DTRT on
|
||||
* the first EIO, but we're not worse than other parts
|
||||
* of the kernel.
|
||||
*/
|
||||
mapping_set_error(mapping, EIO);
|
||||
}
|
||||
|
||||
return me_pagecache_clean(p, pfn);
|
||||
}
|
||||
|
||||
/*
|
||||
* Clean and dirty swap cache.
|
||||
*
|
||||
* Dirty swap cache page is tricky to handle. The page could live both in page
|
||||
* cache and swap cache(ie. page is freshly swapped in). So it could be
|
||||
* referenced concurrently by 2 types of PTEs:
|
||||
* normal PTEs and swap PTEs. We try to handle them consistently by calling
|
||||
* try_to_unmap(TTU_IGNORE_HWPOISON) to convert the normal PTEs to swap PTEs,
|
||||
* and then
|
||||
* - clear dirty bit to prevent IO
|
||||
* - remove from LRU
|
||||
* - but keep in the swap cache, so that when we return to it on
|
||||
* a later page fault, we know the application is accessing
|
||||
* corrupted data and shall be killed (we installed simple
|
||||
* interception code in do_swap_page to catch it).
|
||||
*
|
||||
* Clean swap cache pages can be directly isolated. A later page fault will
|
||||
* bring in the known good data from disk.
|
||||
*/
|
||||
static int me_swapcache_dirty(struct page *p, unsigned long pfn)
|
||||
{
|
||||
int ret = FAILED;
|
||||
|
||||
ClearPageDirty(p);
|
||||
/* Trigger EIO in shmem: */
|
||||
ClearPageUptodate(p);
|
||||
|
||||
if (!isolate_lru_page(p)) {
|
||||
page_cache_release(p);
|
||||
ret = DELAYED;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int me_swapcache_clean(struct page *p, unsigned long pfn)
|
||||
{
|
||||
int ret = FAILED;
|
||||
|
||||
if (!isolate_lru_page(p)) {
|
||||
page_cache_release(p);
|
||||
ret = RECOVERED;
|
||||
}
|
||||
delete_from_swap_cache(p);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Huge pages. Needs work.
|
||||
* Issues:
|
||||
* No rmap support so we cannot find the original mapper. In theory could walk
|
||||
* all MMs and look for the mappings, but that would be non atomic and racy.
|
||||
* Need rmap for hugepages for this. Alternatively we could employ a heuristic,
|
||||
* like just walking the current process and hoping it has it mapped (that
|
||||
* should be usually true for the common "shared database cache" case)
|
||||
* Should handle free huge pages and dequeue them too, but this needs to
|
||||
* handle huge page accounting correctly.
|
||||
*/
|
||||
static int me_huge_page(struct page *p, unsigned long pfn)
|
||||
{
|
||||
return FAILED;
|
||||
}
|
||||
|
||||
/*
|
||||
* Various page states we can handle.
|
||||
*
|
||||
* A page state is defined by its current page->flags bits.
|
||||
* The table matches them in order and calls the right handler.
|
||||
*
|
||||
* This is quite tricky because we can access page at any time
|
||||
* in its live cycle, so all accesses have to be extremly careful.
|
||||
*
|
||||
* This is not complete. More states could be added.
|
||||
* For any missing state don't attempt recovery.
|
||||
*/
|
||||
|
||||
#define dirty (1UL << PG_dirty)
|
||||
#define sc (1UL << PG_swapcache)
|
||||
#define unevict (1UL << PG_unevictable)
|
||||
#define mlock (1UL << PG_mlocked)
|
||||
#define writeback (1UL << PG_writeback)
|
||||
#define lru (1UL << PG_lru)
|
||||
#define swapbacked (1UL << PG_swapbacked)
|
||||
#define head (1UL << PG_head)
|
||||
#define tail (1UL << PG_tail)
|
||||
#define compound (1UL << PG_compound)
|
||||
#define slab (1UL << PG_slab)
|
||||
#define buddy (1UL << PG_buddy)
|
||||
#define reserved (1UL << PG_reserved)
|
||||
|
||||
static struct page_state {
|
||||
unsigned long mask;
|
||||
unsigned long res;
|
||||
char *msg;
|
||||
int (*action)(struct page *p, unsigned long pfn);
|
||||
} error_states[] = {
|
||||
{ reserved, reserved, "reserved kernel", me_ignore },
|
||||
{ buddy, buddy, "free kernel", me_free },
|
||||
|
||||
/*
|
||||
* Could in theory check if slab page is free or if we can drop
|
||||
* currently unused objects without touching them. But just
|
||||
* treat it as standard kernel for now.
|
||||
*/
|
||||
{ slab, slab, "kernel slab", me_kernel },
|
||||
|
||||
#ifdef CONFIG_PAGEFLAGS_EXTENDED
|
||||
{ head, head, "huge", me_huge_page },
|
||||
{ tail, tail, "huge", me_huge_page },
|
||||
#else
|
||||
{ compound, compound, "huge", me_huge_page },
|
||||
#endif
|
||||
|
||||
{ sc|dirty, sc|dirty, "swapcache", me_swapcache_dirty },
|
||||
{ sc|dirty, sc, "swapcache", me_swapcache_clean },
|
||||
|
||||
{ unevict|dirty, unevict|dirty, "unevictable LRU", me_pagecache_dirty},
|
||||
{ unevict, unevict, "unevictable LRU", me_pagecache_clean},
|
||||
|
||||
#ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT
|
||||
{ mlock|dirty, mlock|dirty, "mlocked LRU", me_pagecache_dirty },
|
||||
{ mlock, mlock, "mlocked LRU", me_pagecache_clean },
|
||||
#endif
|
||||
|
||||
{ lru|dirty, lru|dirty, "LRU", me_pagecache_dirty },
|
||||
{ lru|dirty, lru, "clean LRU", me_pagecache_clean },
|
||||
{ swapbacked, swapbacked, "anonymous", me_pagecache_clean },
|
||||
|
||||
/*
|
||||
* Catchall entry: must be at end.
|
||||
*/
|
||||
{ 0, 0, "unknown page state", me_unknown },
|
||||
};
|
||||
|
||||
#undef lru
|
||||
|
||||
static void action_result(unsigned long pfn, char *msg, int result)
|
||||
{
|
||||
struct page *page = NULL;
|
||||
if (pfn_valid(pfn))
|
||||
page = pfn_to_page(pfn);
|
||||
|
||||
printk(KERN_ERR "MCE %#lx: %s%s page recovery: %s\n",
|
||||
pfn,
|
||||
page && PageDirty(page) ? "dirty " : "",
|
||||
msg, action_name[result]);
|
||||
}
|
||||
|
||||
static int page_action(struct page_state *ps, struct page *p,
|
||||
unsigned long pfn, int ref)
|
||||
{
|
||||
int result;
|
||||
|
||||
result = ps->action(p, pfn);
|
||||
action_result(pfn, ps->msg, result);
|
||||
if (page_count(p) != 1 + ref)
|
||||
printk(KERN_ERR
|
||||
"MCE %#lx: %s page still referenced by %d users\n",
|
||||
pfn, ps->msg, page_count(p) - 1);
|
||||
|
||||
/* Could do more checks here if page looks ok */
|
||||
/*
|
||||
* Could adjust zone counters here to correct for the missing page.
|
||||
*/
|
||||
|
||||
return result == RECOVERED ? 0 : -EBUSY;
|
||||
}
|
||||
|
||||
#define N_UNMAP_TRIES 5
|
||||
|
||||
/*
|
||||
* Do all that is necessary to remove user space mappings. Unmap
|
||||
* the pages and send SIGBUS to the processes if the data was dirty.
|
||||
*/
|
||||
static void hwpoison_user_mappings(struct page *p, unsigned long pfn,
|
||||
int trapno)
|
||||
{
|
||||
enum ttu_flags ttu = TTU_UNMAP | TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS;
|
||||
struct address_space *mapping;
|
||||
LIST_HEAD(tokill);
|
||||
int ret;
|
||||
int i;
|
||||
int kill = 1;
|
||||
|
||||
if (PageReserved(p) || PageCompound(p) || PageSlab(p))
|
||||
return;
|
||||
|
||||
if (!PageLRU(p))
|
||||
lru_add_drain_all();
|
||||
|
||||
/*
|
||||
* This check implies we don't kill processes if their pages
|
||||
* are in the swap cache early. Those are always late kills.
|
||||
*/
|
||||
if (!page_mapped(p))
|
||||
return;
|
||||
|
||||
if (PageSwapCache(p)) {
|
||||
printk(KERN_ERR
|
||||
"MCE %#lx: keeping poisoned page in swap cache\n", pfn);
|
||||
ttu |= TTU_IGNORE_HWPOISON;
|
||||
}
|
||||
|
||||
/*
|
||||
* Propagate the dirty bit from PTEs to struct page first, because we
|
||||
* need this to decide if we should kill or just drop the page.
|
||||
*/
|
||||
mapping = page_mapping(p);
|
||||
if (!PageDirty(p) && mapping && mapping_cap_writeback_dirty(mapping)) {
|
||||
if (page_mkclean(p)) {
|
||||
SetPageDirty(p);
|
||||
} else {
|
||||
kill = 0;
|
||||
ttu |= TTU_IGNORE_HWPOISON;
|
||||
printk(KERN_INFO
|
||||
"MCE %#lx: corrupted page was clean: dropped without side effects\n",
|
||||
pfn);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* First collect all the processes that have the page
|
||||
* mapped in dirty form. This has to be done before try_to_unmap,
|
||||
* because ttu takes the rmap data structures down.
|
||||
*
|
||||
* Error handling: We ignore errors here because
|
||||
* there's nothing that can be done.
|
||||
*/
|
||||
if (kill)
|
||||
collect_procs(p, &tokill);
|
||||
|
||||
/*
|
||||
* try_to_unmap can fail temporarily due to races.
|
||||
* Try a few times (RED-PEN better strategy?)
|
||||
*/
|
||||
for (i = 0; i < N_UNMAP_TRIES; i++) {
|
||||
ret = try_to_unmap(p, ttu);
|
||||
if (ret == SWAP_SUCCESS)
|
||||
break;
|
||||
pr_debug("MCE %#lx: try_to_unmap retry needed %d\n", pfn, ret);
|
||||
}
|
||||
|
||||
if (ret != SWAP_SUCCESS)
|
||||
printk(KERN_ERR "MCE %#lx: failed to unmap page (mapcount=%d)\n",
|
||||
pfn, page_mapcount(p));
|
||||
|
||||
/*
|
||||
* Now that the dirty bit has been propagated to the
|
||||
* struct page and all unmaps done we can decide if
|
||||
* killing is needed or not. Only kill when the page
|
||||
* was dirty, otherwise the tokill list is merely
|
||||
* freed. When there was a problem unmapping earlier
|
||||
* use a more force-full uncatchable kill to prevent
|
||||
* any accesses to the poisoned memory.
|
||||
*/
|
||||
kill_procs_ao(&tokill, !!PageDirty(p), trapno,
|
||||
ret != SWAP_SUCCESS, pfn);
|
||||
}
|
||||
|
||||
int __memory_failure(unsigned long pfn, int trapno, int ref)
|
||||
{
|
||||
struct page_state *ps;
|
||||
struct page *p;
|
||||
int res;
|
||||
|
||||
if (!sysctl_memory_failure_recovery)
|
||||
panic("Memory failure from trap %d on page %lx", trapno, pfn);
|
||||
|
||||
if (!pfn_valid(pfn)) {
|
||||
action_result(pfn, "memory outside kernel control", IGNORED);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
p = pfn_to_page(pfn);
|
||||
if (TestSetPageHWPoison(p)) {
|
||||
action_result(pfn, "already hardware poisoned", IGNORED);
|
||||
return 0;
|
||||
}
|
||||
|
||||
atomic_long_add(1, &mce_bad_pages);
|
||||
|
||||
/*
|
||||
* We need/can do nothing about count=0 pages.
|
||||
* 1) it's a free page, and therefore in safe hand:
|
||||
* prep_new_page() will be the gate keeper.
|
||||
* 2) it's part of a non-compound high order page.
|
||||
* Implies some kernel user: cannot stop them from
|
||||
* R/W the page; let's pray that the page has been
|
||||
* used and will be freed some time later.
|
||||
* In fact it's dangerous to directly bump up page count from 0,
|
||||
* that may make page_freeze_refs()/page_unfreeze_refs() mismatch.
|
||||
*/
|
||||
if (!get_page_unless_zero(compound_head(p))) {
|
||||
action_result(pfn, "free or high order kernel", IGNORED);
|
||||
return PageBuddy(compound_head(p)) ? 0 : -EBUSY;
|
||||
}
|
||||
|
||||
/*
|
||||
* Lock the page and wait for writeback to finish.
|
||||
* It's very difficult to mess with pages currently under IO
|
||||
* and in many cases impossible, so we just avoid it here.
|
||||
*/
|
||||
lock_page_nosync(p);
|
||||
wait_on_page_writeback(p);
|
||||
|
||||
/*
|
||||
* Now take care of user space mappings.
|
||||
*/
|
||||
hwpoison_user_mappings(p, pfn, trapno);
|
||||
|
||||
/*
|
||||
* Torn down by someone else?
|
||||
*/
|
||||
if (PageLRU(p) && !PageSwapCache(p) && p->mapping == NULL) {
|
||||
action_result(pfn, "already truncated LRU", IGNORED);
|
||||
res = 0;
|
||||
goto out;
|
||||
}
|
||||
|
||||
res = -EBUSY;
|
||||
for (ps = error_states;; ps++) {
|
||||
if ((p->flags & ps->mask) == ps->res) {
|
||||
res = page_action(ps, p, pfn, ref);
|
||||
break;
|
||||
}
|
||||
}
|
||||
out:
|
||||
unlock_page(p);
|
||||
return res;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(__memory_failure);
|
||||
|
||||
/**
|
||||
* memory_failure - Handle memory failure of a page.
|
||||
* @pfn: Page Number of the corrupted page
|
||||
* @trapno: Trap number reported in the signal to user space.
|
||||
*
|
||||
* This function is called by the low level machine check code
|
||||
* of an architecture when it detects hardware memory corruption
|
||||
* of a page. It tries its best to recover, which includes
|
||||
* dropping pages, killing processes etc.
|
||||
*
|
||||
* The function is primarily of use for corruptions that
|
||||
* happen outside the current execution context (e.g. when
|
||||
* detected by a background scrubber)
|
||||
*
|
||||
* Must run in process context (e.g. a work queue) with interrupts
|
||||
* enabled and no spinlocks hold.
|
||||
*/
|
||||
void memory_failure(unsigned long pfn, int trapno)
|
||||
{
|
||||
__memory_failure(pfn, trapno, 0);
|
||||
}
|
||||
24
mm/memory.c
24
mm/memory.c
@ -1325,7 +1325,8 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
|
||||
if (ret & VM_FAULT_ERROR) {
|
||||
if (ret & VM_FAULT_OOM)
|
||||
return i ? i : -ENOMEM;
|
||||
else if (ret & VM_FAULT_SIGBUS)
|
||||
if (ret &
|
||||
(VM_FAULT_HWPOISON|VM_FAULT_SIGBUS))
|
||||
return i ? i : -EFAULT;
|
||||
BUG();
|
||||
}
|
||||
@ -2559,8 +2560,15 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
|
||||
goto out;
|
||||
|
||||
entry = pte_to_swp_entry(orig_pte);
|
||||
if (is_migration_entry(entry)) {
|
||||
migration_entry_wait(mm, pmd, address);
|
||||
if (unlikely(non_swap_entry(entry))) {
|
||||
if (is_migration_entry(entry)) {
|
||||
migration_entry_wait(mm, pmd, address);
|
||||
} else if (is_hwpoison_entry(entry)) {
|
||||
ret = VM_FAULT_HWPOISON;
|
||||
} else {
|
||||
print_bad_pte(vma, address, orig_pte, NULL);
|
||||
ret = VM_FAULT_OOM;
|
||||
}
|
||||
goto out;
|
||||
}
|
||||
delayacct_set_flag(DELAYACCT_PF_SWAPIN);
|
||||
@ -2584,6 +2592,10 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
|
||||
/* Had to read the page from swap area: Major fault */
|
||||
ret = VM_FAULT_MAJOR;
|
||||
count_vm_event(PGMAJFAULT);
|
||||
} else if (PageHWPoison(page)) {
|
||||
ret = VM_FAULT_HWPOISON;
|
||||
delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
|
||||
goto out;
|
||||
}
|
||||
|
||||
lock_page(page);
|
||||
@ -2760,6 +2772,12 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
|
||||
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))
|
||||
return ret;
|
||||
|
||||
if (unlikely(PageHWPoison(vmf.page))) {
|
||||
if (ret & VM_FAULT_LOCKED)
|
||||
unlock_page(vmf.page);
|
||||
return VM_FAULT_HWPOISON;
|
||||
}
|
||||
|
||||
/*
|
||||
* For consistency in subsequent calls, make the faulted page always
|
||||
* locked.
|
||||
|
||||
@ -675,7 +675,7 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
|
||||
}
|
||||
|
||||
/* Establish migration ptes or remove ptes */
|
||||
try_to_unmap(page, 1);
|
||||
try_to_unmap(page, TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS);
|
||||
|
||||
skip_unmap:
|
||||
if (!page_mapped(page))
|
||||
|
||||
@ -1149,6 +1149,13 @@ int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page)
|
||||
EXPORT_SYMBOL(redirty_page_for_writepage);
|
||||
|
||||
/*
|
||||
* Dirty a page.
|
||||
*
|
||||
* For pages with a mapping this should be done under the page lock
|
||||
* for the benefit of asynchronous memory errors who prefer a consistent
|
||||
* dirty state. This rule can be broken in some special cases,
|
||||
* but should be better not to.
|
||||
*
|
||||
* If the mapping doesn't provide a set_page_dirty a_op, then
|
||||
* just fall through and assume that it wants buffer_heads.
|
||||
*/
|
||||
|
||||
@ -234,6 +234,12 @@ static void bad_page(struct page *page)
|
||||
static unsigned long nr_shown;
|
||||
static unsigned long nr_unshown;
|
||||
|
||||
/* Don't complain about poisoned pages */
|
||||
if (PageHWPoison(page)) {
|
||||
__ClearPageBuddy(page);
|
||||
return;
|
||||
}
|
||||
|
||||
/*
|
||||
* Allow a burst of 60 reports, then keep quiet for that minute;
|
||||
* or allow a steady drip of one report per second.
|
||||
@ -666,7 +672,7 @@ static inline void expand(struct zone *zone, struct page *page,
|
||||
/*
|
||||
* This page is about to be returned from the page allocator
|
||||
*/
|
||||
static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
|
||||
static inline int check_new_page(struct page *page)
|
||||
{
|
||||
if (unlikely(page_mapcount(page) |
|
||||
(page->mapping != NULL) |
|
||||
@ -675,6 +681,18 @@ static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
|
||||
bad_page(page);
|
||||
return 1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < (1 << order); i++) {
|
||||
struct page *p = page + i;
|
||||
if (unlikely(check_new_page(p)))
|
||||
return 1;
|
||||
}
|
||||
|
||||
set_page_private(page, 0);
|
||||
set_page_refcounted(page);
|
||||
|
||||
60
mm/rmap.c
60
mm/rmap.c
@ -36,6 +36,11 @@
|
||||
* mapping->tree_lock (widely used, in set_page_dirty,
|
||||
* in arch-dependent flush_dcache_mmap_lock,
|
||||
* within inode_lock in __sync_single_inode)
|
||||
*
|
||||
* (code doesn't rely on that order so it could be switched around)
|
||||
* ->tasklist_lock
|
||||
* anon_vma->lock (memory_failure, collect_procs_anon)
|
||||
* pte map lock
|
||||
*/
|
||||
|
||||
#include <linux/mm.h>
|
||||
@ -191,7 +196,7 @@ void __init anon_vma_init(void)
|
||||
* Getting a lock on a stable anon_vma from a page off the LRU is
|
||||
* tricky: page_lock_anon_vma rely on RCU to guard against the races.
|
||||
*/
|
||||
static struct anon_vma *page_lock_anon_vma(struct page *page)
|
||||
struct anon_vma *page_lock_anon_vma(struct page *page)
|
||||
{
|
||||
struct anon_vma *anon_vma;
|
||||
unsigned long anon_mapping;
|
||||
@ -211,7 +216,7 @@ out:
|
||||
return NULL;
|
||||
}
|
||||
|
||||
static void page_unlock_anon_vma(struct anon_vma *anon_vma)
|
||||
void page_unlock_anon_vma(struct anon_vma *anon_vma)
|
||||
{
|
||||
spin_unlock(&anon_vma->lock);
|
||||
rcu_read_unlock();
|
||||
@ -311,7 +316,7 @@ pte_t *page_check_address(struct page *page, struct mm_struct *mm,
|
||||
* if the page is not mapped into the page tables of this VMA. Only
|
||||
* valid for normal file or anonymous VMAs.
|
||||
*/
|
||||
static int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma)
|
||||
int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma)
|
||||
{
|
||||
unsigned long address;
|
||||
pte_t *pte;
|
||||
@ -756,7 +761,7 @@ void page_remove_rmap(struct page *page)
|
||||
* repeatedly from either try_to_unmap_anon or try_to_unmap_file.
|
||||
*/
|
||||
static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
|
||||
int migration)
|
||||
enum ttu_flags flags)
|
||||
{
|
||||
struct mm_struct *mm = vma->vm_mm;
|
||||
unsigned long address;
|
||||
@ -778,11 +783,13 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
|
||||
* If it's recently referenced (perhaps page_referenced
|
||||
* skipped over this mm) then we should reactivate it.
|
||||
*/
|
||||
if (!migration) {
|
||||
if (!(flags & TTU_IGNORE_MLOCK)) {
|
||||
if (vma->vm_flags & VM_LOCKED) {
|
||||
ret = SWAP_MLOCK;
|
||||
goto out_unmap;
|
||||
}
|
||||
}
|
||||
if (!(flags & TTU_IGNORE_ACCESS)) {
|
||||
if (ptep_clear_flush_young_notify(vma, address, pte)) {
|
||||
ret = SWAP_FAIL;
|
||||
goto out_unmap;
|
||||
@ -800,7 +807,14 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
|
||||
/* Update high watermark before we lower rss */
|
||||
update_hiwater_rss(mm);
|
||||
|
||||
if (PageAnon(page)) {
|
||||
if (PageHWPoison(page) && !(flags & TTU_IGNORE_HWPOISON)) {
|
||||
if (PageAnon(page))
|
||||
dec_mm_counter(mm, anon_rss);
|
||||
else
|
||||
dec_mm_counter(mm, file_rss);
|
||||
set_pte_at(mm, address, pte,
|
||||
swp_entry_to_pte(make_hwpoison_entry(page)));
|
||||
} else if (PageAnon(page)) {
|
||||
swp_entry_t entry = { .val = page_private(page) };
|
||||
|
||||
if (PageSwapCache(page)) {
|
||||
@ -822,12 +836,12 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
|
||||
* pte. do_swap_page() will wait until the migration
|
||||
* pte is removed and then restart fault handling.
|
||||
*/
|
||||
BUG_ON(!migration);
|
||||
BUG_ON(TTU_ACTION(flags) != TTU_MIGRATION);
|
||||
entry = make_migration_entry(page, pte_write(pteval));
|
||||
}
|
||||
set_pte_at(mm, address, pte, swp_entry_to_pte(entry));
|
||||
BUG_ON(pte_file(*pte));
|
||||
} else if (PAGE_MIGRATION && migration) {
|
||||
} else if (PAGE_MIGRATION && (TTU_ACTION(flags) == TTU_MIGRATION)) {
|
||||
/* Establish migration entry for a file page */
|
||||
swp_entry_t entry;
|
||||
entry = make_migration_entry(page, pte_write(pteval));
|
||||
@ -996,12 +1010,13 @@ static int try_to_mlock_page(struct page *page, struct vm_area_struct *vma)
|
||||
* vm_flags for that VMA. That should be OK, because that vma shouldn't be
|
||||
* 'LOCKED.
|
||||
*/
|
||||
static int try_to_unmap_anon(struct page *page, int unlock, int migration)
|
||||
static int try_to_unmap_anon(struct page *page, enum ttu_flags flags)
|
||||
{
|
||||
struct anon_vma *anon_vma;
|
||||
struct vm_area_struct *vma;
|
||||
unsigned int mlocked = 0;
|
||||
int ret = SWAP_AGAIN;
|
||||
int unlock = TTU_ACTION(flags) == TTU_MUNLOCK;
|
||||
|
||||
if (MLOCK_PAGES && unlikely(unlock))
|
||||
ret = SWAP_SUCCESS; /* default for try_to_munlock() */
|
||||
@ -1017,7 +1032,7 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration)
|
||||
continue; /* must visit all unlocked vmas */
|
||||
ret = SWAP_MLOCK; /* saw at least one mlocked vma */
|
||||
} else {
|
||||
ret = try_to_unmap_one(page, vma, migration);
|
||||
ret = try_to_unmap_one(page, vma, flags);
|
||||
if (ret == SWAP_FAIL || !page_mapped(page))
|
||||
break;
|
||||
}
|
||||
@ -1041,8 +1056,7 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration)
|
||||
/**
|
||||
* try_to_unmap_file - unmap/unlock file page using the object-based rmap method
|
||||
* @page: the page to unmap/unlock
|
||||
* @unlock: request for unlock rather than unmap [unlikely]
|
||||
* @migration: unmapping for migration - ignored if @unlock
|
||||
* @flags: action and flags
|
||||
*
|
||||
* Find all the mappings of a page using the mapping pointer and the vma chains
|
||||
* contained in the address_space struct it points to.
|
||||
@ -1054,7 +1068,7 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration)
|
||||
* vm_flags for that VMA. That should be OK, because that vma shouldn't be
|
||||
* 'LOCKED.
|
||||
*/
|
||||
static int try_to_unmap_file(struct page *page, int unlock, int migration)
|
||||
static int try_to_unmap_file(struct page *page, enum ttu_flags flags)
|
||||
{
|
||||
struct address_space *mapping = page->mapping;
|
||||
pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
|
||||
@ -1066,6 +1080,7 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration)
|
||||
unsigned long max_nl_size = 0;
|
||||
unsigned int mapcount;
|
||||
unsigned int mlocked = 0;
|
||||
int unlock = TTU_ACTION(flags) == TTU_MUNLOCK;
|
||||
|
||||
if (MLOCK_PAGES && unlikely(unlock))
|
||||
ret = SWAP_SUCCESS; /* default for try_to_munlock() */
|
||||
@ -1078,7 +1093,7 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration)
|
||||
continue; /* must visit all vmas */
|
||||
ret = SWAP_MLOCK;
|
||||
} else {
|
||||
ret = try_to_unmap_one(page, vma, migration);
|
||||
ret = try_to_unmap_one(page, vma, flags);
|
||||
if (ret == SWAP_FAIL || !page_mapped(page))
|
||||
goto out;
|
||||
}
|
||||
@ -1103,7 +1118,8 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration)
|
||||
ret = SWAP_MLOCK; /* leave mlocked == 0 */
|
||||
goto out; /* no need to look further */
|
||||
}
|
||||
if (!MLOCK_PAGES && !migration && (vma->vm_flags & VM_LOCKED))
|
||||
if (!MLOCK_PAGES && !(flags & TTU_IGNORE_MLOCK) &&
|
||||
(vma->vm_flags & VM_LOCKED))
|
||||
continue;
|
||||
cursor = (unsigned long) vma->vm_private_data;
|
||||
if (cursor > max_nl_cursor)
|
||||
@ -1137,7 +1153,7 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration)
|
||||
do {
|
||||
list_for_each_entry(vma, &mapping->i_mmap_nonlinear,
|
||||
shared.vm_set.list) {
|
||||
if (!MLOCK_PAGES && !migration &&
|
||||
if (!MLOCK_PAGES && !(flags & TTU_IGNORE_MLOCK) &&
|
||||
(vma->vm_flags & VM_LOCKED))
|
||||
continue;
|
||||
cursor = (unsigned long) vma->vm_private_data;
|
||||
@ -1177,7 +1193,7 @@ out:
|
||||
/**
|
||||
* try_to_unmap - try to remove all page table mappings to a page
|
||||
* @page: the page to get unmapped
|
||||
* @migration: migration flag
|
||||
* @flags: action and flags
|
||||
*
|
||||
* Tries to remove all the page table entries which are mapping this
|
||||
* page, used in the pageout path. Caller must hold the page lock.
|
||||
@ -1188,16 +1204,16 @@ out:
|
||||
* SWAP_FAIL - the page is unswappable
|
||||
* SWAP_MLOCK - page is mlocked.
|
||||
*/
|
||||
int try_to_unmap(struct page *page, int migration)
|
||||
int try_to_unmap(struct page *page, enum ttu_flags flags)
|
||||
{
|
||||
int ret;
|
||||
|
||||
BUG_ON(!PageLocked(page));
|
||||
|
||||
if (PageAnon(page))
|
||||
ret = try_to_unmap_anon(page, 0, migration);
|
||||
ret = try_to_unmap_anon(page, flags);
|
||||
else
|
||||
ret = try_to_unmap_file(page, 0, migration);
|
||||
ret = try_to_unmap_file(page, flags);
|
||||
if (ret != SWAP_MLOCK && !page_mapped(page))
|
||||
ret = SWAP_SUCCESS;
|
||||
return ret;
|
||||
@ -1222,8 +1238,8 @@ int try_to_munlock(struct page *page)
|
||||
VM_BUG_ON(!PageLocked(page) || PageLRU(page));
|
||||
|
||||
if (PageAnon(page))
|
||||
return try_to_unmap_anon(page, 1, 0);
|
||||
return try_to_unmap_anon(page, TTU_MUNLOCK);
|
||||
else
|
||||
return try_to_unmap_file(page, 1, 0);
|
||||
return try_to_unmap_file(page, TTU_MUNLOCK);
|
||||
}
|
||||
|
||||
|
||||
@ -1633,8 +1633,8 @@ shmem_write_end(struct file *file, struct address_space *mapping,
|
||||
if (pos + copied > inode->i_size)
|
||||
i_size_write(inode, pos + copied);
|
||||
|
||||
unlock_page(page);
|
||||
set_page_dirty(page);
|
||||
unlock_page(page);
|
||||
page_cache_release(page);
|
||||
|
||||
return copied;
|
||||
@ -1971,13 +1971,13 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
|
||||
iput(inode);
|
||||
return error;
|
||||
}
|
||||
unlock_page(page);
|
||||
inode->i_mapping->a_ops = &shmem_aops;
|
||||
inode->i_op = &shmem_symlink_inode_operations;
|
||||
kaddr = kmap_atomic(page, KM_USER0);
|
||||
memcpy(kaddr, symname, len);
|
||||
kunmap_atomic(kaddr, KM_USER0);
|
||||
set_page_dirty(page);
|
||||
unlock_page(page);
|
||||
page_cache_release(page);
|
||||
}
|
||||
if (dir->i_mode & S_ISGID)
|
||||
@ -2420,6 +2420,7 @@ static const struct address_space_operations shmem_aops = {
|
||||
.write_end = shmem_write_end,
|
||||
#endif
|
||||
.migratepage = migrate_page,
|
||||
.error_remove_page = generic_error_remove_page,
|
||||
};
|
||||
|
||||
static const struct file_operations shmem_file_operations = {
|
||||
|
||||
@ -699,7 +699,7 @@ int free_swap_and_cache(swp_entry_t entry)
|
||||
struct swap_info_struct *p;
|
||||
struct page *page = NULL;
|
||||
|
||||
if (is_migration_entry(entry))
|
||||
if (non_swap_entry(entry))
|
||||
return 1;
|
||||
|
||||
p = swap_info_get(entry);
|
||||
@ -2085,7 +2085,7 @@ static int __swap_duplicate(swp_entry_t entry, bool cache)
|
||||
int count;
|
||||
bool has_cache;
|
||||
|
||||
if (is_migration_entry(entry))
|
||||
if (non_swap_entry(entry))
|
||||
return -EINVAL;
|
||||
|
||||
type = swp_type(entry);
|
||||
|
||||
@ -93,11 +93,11 @@ EXPORT_SYMBOL(cancel_dirty_page);
|
||||
* its lock, b) when a concurrent invalidate_mapping_pages got there first and
|
||||
* c) when tmpfs swizzles a page between a tmpfs inode and swapper_space.
|
||||
*/
|
||||
static void
|
||||
static int
|
||||
truncate_complete_page(struct address_space *mapping, struct page *page)
|
||||
{
|
||||
if (page->mapping != mapping)
|
||||
return;
|
||||
return -EIO;
|
||||
|
||||
if (page_has_private(page))
|
||||
do_invalidatepage(page, 0);
|
||||
@ -108,6 +108,7 @@ truncate_complete_page(struct address_space *mapping, struct page *page)
|
||||
remove_from_page_cache(page);
|
||||
ClearPageMappedToDisk(page);
|
||||
page_cache_release(page); /* pagecache ref */
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
@ -135,6 +136,51 @@ invalidate_complete_page(struct address_space *mapping, struct page *page)
|
||||
return ret;
|
||||
}
|
||||
|
||||
int truncate_inode_page(struct address_space *mapping, struct page *page)
|
||||
{
|
||||
if (page_mapped(page)) {
|
||||
unmap_mapping_range(mapping,
|
||||
(loff_t)page->index << PAGE_CACHE_SHIFT,
|
||||
PAGE_CACHE_SIZE, 0);
|
||||
}
|
||||
return truncate_complete_page(mapping, page);
|
||||
}
|
||||
|
||||
/*
|
||||
* Used to get rid of pages on hardware memory corruption.
|
||||
*/
|
||||
int generic_error_remove_page(struct address_space *mapping, struct page *page)
|
||||
{
|
||||
if (!mapping)
|
||||
return -EINVAL;
|
||||
/*
|
||||
* Only punch for normal data pages for now.
|
||||
* Handling other types like directories would need more auditing.
|
||||
*/
|
||||
if (!S_ISREG(mapping->host->i_mode))
|
||||
return -EIO;
|
||||
return truncate_inode_page(mapping, page);
|
||||
}
|
||||
EXPORT_SYMBOL(generic_error_remove_page);
|
||||
|
||||
/*
|
||||
* Safely invalidate one page from its pagecache mapping.
|
||||
* It only drops clean, unused pages. The page must be locked.
|
||||
*
|
||||
* Returns 1 if the page is successfully invalidated, otherwise 0.
|
||||
*/
|
||||
int invalidate_inode_page(struct page *page)
|
||||
{
|
||||
struct address_space *mapping = page_mapping(page);
|
||||
if (!mapping)
|
||||
return 0;
|
||||
if (PageDirty(page) || PageWriteback(page))
|
||||
return 0;
|
||||
if (page_mapped(page))
|
||||
return 0;
|
||||
return invalidate_complete_page(mapping, page);
|
||||
}
|
||||
|
||||
/**
|
||||
* truncate_inode_pages - truncate range of pages specified by start & end byte offsets
|
||||
* @mapping: mapping to truncate
|
||||
@ -196,12 +242,7 @@ void truncate_inode_pages_range(struct address_space *mapping,
|
||||
unlock_page(page);
|
||||
continue;
|
||||
}
|
||||
if (page_mapped(page)) {
|
||||
unmap_mapping_range(mapping,
|
||||
(loff_t)page_index<<PAGE_CACHE_SHIFT,
|
||||
PAGE_CACHE_SIZE, 0);
|
||||
}
|
||||
truncate_complete_page(mapping, page);
|
||||
truncate_inode_page(mapping, page);
|
||||
unlock_page(page);
|
||||
}
|
||||
pagevec_release(&pvec);
|
||||
@ -238,15 +279,10 @@ void truncate_inode_pages_range(struct address_space *mapping,
|
||||
break;
|
||||
lock_page(page);
|
||||
wait_on_page_writeback(page);
|
||||
if (page_mapped(page)) {
|
||||
unmap_mapping_range(mapping,
|
||||
(loff_t)page->index<<PAGE_CACHE_SHIFT,
|
||||
PAGE_CACHE_SIZE, 0);
|
||||
}
|
||||
truncate_inode_page(mapping, page);
|
||||
if (page->index > next)
|
||||
next = page->index;
|
||||
next++;
|
||||
truncate_complete_page(mapping, page);
|
||||
unlock_page(page);
|
||||
}
|
||||
pagevec_release(&pvec);
|
||||
@ -311,12 +347,8 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping,
|
||||
if (lock_failed)
|
||||
continue;
|
||||
|
||||
if (PageDirty(page) || PageWriteback(page))
|
||||
goto unlock;
|
||||
if (page_mapped(page))
|
||||
goto unlock;
|
||||
ret += invalidate_complete_page(mapping, page);
|
||||
unlock:
|
||||
ret += invalidate_inode_page(page);
|
||||
|
||||
unlock_page(page);
|
||||
if (next > end)
|
||||
break;
|
||||
|
||||
@ -663,7 +663,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
|
||||
* processes. Try to unmap it here.
|
||||
*/
|
||||
if (page_mapped(page) && mapping) {
|
||||
switch (try_to_unmap(page, 0)) {
|
||||
switch (try_to_unmap(page, TTU_UNMAP)) {
|
||||
case SWAP_FAIL:
|
||||
goto activate_locked;
|
||||
case SWAP_AGAIN:
|
||||
|
||||
Loading…
Reference in New Issue
Block a user