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Now that all the grouping is done with RB trees, we no longer need
group_entry and can replace the whole thing with sibling_list.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When switching to ACPI HW reduced platforms we still want to initialize timers.
Override x86_init.acpi.reduced_hw_init to achieve that.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-acpi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180220180506.65523-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some ACPI hardware reduced platforms need to initialize certain devices
defined by the ACPI hardware specification even though in principle
those devices should not be present in an ACPI hardware reduced platform.
To allow that to happen, make it possible to override the generic
x86_init callbacks and provide a custom legacy_pic value, add a new
->reduced_hw_early_init() callback to struct x86_init_acpi and make
acpi_reduced_hw_init() use it.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-acpi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180220180506.65523-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This is a preparation patch to allow override the hardware reduced
initialization on ACPI enabled platforms.
No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-acpi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180220180506.65523-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The comments are factored out from the code changes to make them
easier to read. Add them separately to explain some non-obvious
aspects.
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kasan-dev@googlegroups.com
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/cc595efc644bb905407012d82d3eb8bac3368e7a.1517246437.git.dvyukov@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add arch_ prefix to all atomic operations and include
<asm-generic/atomic-instrumented.h>. This will allow
to add KASAN instrumentation to all atomic ops.
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kasan-dev@googlegroups.com
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/54f0eb64260b84199e538652e079a89b5423ad41.1517246437.git.dvyukov@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Intel PCONFIG targets are enumerated via new CPUID leaf 0x1b. This patch
detects all supported targets of PCONFIG and implements helper to check
if the target is supported.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kai Huang <kai.huang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180305162610.37510-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
IA32_TME_ACTIVATE MSR (0x982) can be used to check if BIOS has enabled
TME and MKTME. It includes which encryption policy/algorithm is selected
for TME or available for MKTME. For MKTME, the MSR also enumerates how
many KeyIDs are available.
We would need to exclude KeyID bits from physical address bits.
detect_tme() would adjust cpuinfo_x86::x86_phys_bits accordingly.
We have to do this even if we are not going to use KeyID bits
ourself. VM guests still have to know that these bits are not usable
for physical address.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kai Huang <kai.huang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180305162610.37510-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch addresses a shortcoming in current boot process on machines
that supports 5-level paging.
If a bootloader enables 64-bit mode with 4-level paging, we might need to
switch over to 5-level paging. The switching requires the disabling
paging. It works fine if kernel itself is loaded below 4G.
But if the bootloader put the kernel above 4G (not sure if anybody does
this), we would lose control as soon as paging is disabled, because the
code becomes unreachable to the CPU.
This patch implements a trampoline in lower memory to handle this
situation.
We only need the memory for a very short time, until the main kernel
image sets up own page tables.
We go through the trampoline even if we don't have to: if we're already
in 5-level paging mode or if we don't need to switch to it. This way the
trampoline gets tested on every boot.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If a bootloader enables 64-bit mode with 4-level paging, we might need to
switch over to 5-level paging. The switching requires the disabling
paging. It works fine if kernel itself is loaded below 4G.
But if the bootloader put the kernel above 4G (i.e. in kexec() case),
we would lose control as soon as paging is disabled, because the code
becomes unreachable to the CPU.
To handle the situation, we need a trampoline in lower memory that would
take care of switching on 5-level paging.
Apart from the trampoline code itself we also need a place to store
top-level page table in lower memory as we don't have a way to load
64-bit values into CR3 in 32-bit mode. We only really need 8 bytes there
as we only use the very first entry of the page table. But we allocate a
whole page anyway.
This patch switches 32-bit code to use page table in trampoline memory.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As the first step on using trampoline memory, let's make 32-bit code use
stack there.
Separate stack is required to return back from trampoline and we cannot
user stack from 64-bit mode as it may be above 4G.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When kernel starts in 64-bit mode we inherit the GDT from the bootloader.
It may cause a problem if the GDT doesn't have a 32-bit code segment
where we expect it to be.
Load our own GDT with known segments.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use helper function efi_switch_mm() to switch to/from efi_mm when
invoking any UEFI runtime services.
Likewise, we need to switch back to previous mm (mm context stolen
by efi_mm) after the above calls return successfully. We can use
efi_switch_mm() helper function only with x86_64 kernel and
"efi=old_map" disabled because, x86_32 and efi=old_map do not use
efi_pgd, rather they use swapper_pg_dir.
Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
[ardb: add #include of sched/task.h for task_lock/_unlock]
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-efi@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In 4-level paging mode, native_set_p4d() updates the entry in the top-level
page table. With PTI, update to the top-level kernel page table requires
update to the userspace copy of the table as well, using pti_set_user_pgd().
native_set_p4d() uses p4d_val() and pgd_val() to convert types between
p4d_t and pgd_t.
p4d_val() and pgd_val() are paravirtualized and we must not use them in
native helpers, as they crash the boot in paravirtualized environments.
Replace p4d_val() and pgd_val() with native_p4d_val() and
native_pgd_val() in native_set_p4d().
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 91f606a8fa68 ("x86/mm: Replace compile-time checks for 5-level paging with runtime-time checks")
Link: http://lkml.kernel.org/r/20180305081641.4290-1-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that we unambiguously build the entire kernel with -fshort-wchar,
it is no longer necessary to open code efi_char16_t[] initializers as
arrays of characters, and we can move to the L"xxx" notation instead.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180312084500.10764-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Presently, only ARM uses mm_struct to manage EFI page tables and EFI
runtime region mappings. As this is the preferred approach, let's make
this data structure common across architectures. Specially, for x86,
using this data structure improves code maintainability and readability.
Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
[ardb: don't #include the world to get a declaration of struct mm_struct]
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180312084500.10764-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit in x86/mm changed EFI code:
116fef640859: x86/mm/dump_pagetables: Add the EFI pagetable to the debugfs 'page_tables' directory
So merge in that commit plus its dependencies, before continuing with
EFI work.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
User-space utilities examining crash-kernels need to know if the
crashed kernel was in 5-level paging mode or not.
So write 'pgtable_l5_enabled' to vmcoreinfo, which covers these
three cases:
pgtable_l5_enabled == 0 when:
- Compiled with !CONFIG_X86_5LEVEL
- Compiled with CONFIG_X86_5LEVEL=y while CPU has no 'la57' flag
pgtable_l5_enabled != 0 when:
- Compiled with CONFIG_X86_5LEVEL=y and CPU has 'la57' flag
Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: douly.fnst@cn.fujitsu.com
Cc: dyoung@redhat.com
Cc: ebiederm@xmission.com
Cc: kirill.shutemov@linux.intel.com
Cc: vgoyal@redhat.com
Link: http://lkml.kernel.org/r/20180302051801.19594-1-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If trampoline code would need to switch between 4- and 5-level paging
modes, we have to use a page table in trampoline memory.
Having it in trampoline memory guarantees that it's below 4G and we can
point CR3 to it from 32-bit trampoline code.
We only use the page table if the desired paging mode doesn't match the
mode we are in. Otherwise the page table is unused and trampoline code
wouldn't touch CR3.
For 4- to 5-level paging transition, we set up current (4-level paging)
CR3 as the first and the only entry in a new top-level page table.
For 5- to 4-level paging transition, copy page table pointed by first
entry in the current top-level page table as our new top-level page
table.
If the page table is used by trampoline we would need to copy it to new
page table outside trampoline and update CR3 before restoring trampoline
memory.
Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-6-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The memory area we found for trampoline shouldn't contain anything
useful. But let's preserve the data anyway. Just to be on safe side.
paging_prepare() would save the data into a buffer.
cleanup_trampoline() would restore it back once we are done with the
trampoline.
Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If a bootloader enables 64-bit mode with 4-level paging, we might need to
switch over to 5-level paging. The switching requires the disabling of
paging, which works fine if kernel itself is loaded below 4G.
But if the bootloader puts the kernel above 4G (not sure if anybody does
this), we would lose control as soon as paging is disabled, because the
code becomes unreachable to the CPU.
To handle the situation, we need a trampoline in lower memory that would
take care of switching on 5-level paging.
This patch finds a spot in low memory for a trampoline.
The heuristic is based on code in reserve_bios_regions().
We find the end of low memory based on BIOS and EBDA start addresses.
The trampoline is put just before end of low memory. It's mimic approach
taken to allocate memory for realtime trampoline.
Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86/pti updates from Thomas Gleixner:
"Yet another pile of melted spectrum related updates:
- Drop native vsyscall support finally as it causes more trouble than
benefit.
- Make microcode loading more robust. There were a few issues
especially related to late loading which are now surfacing because
late loading of the IB* microcodes addressing spectre issues has
become more widely used.
- Simplify and robustify the syscall handling in the entry code
- Prevent kprobes on the entry trampoline code which lead to kernel
crashes when the probe hits before CR3 is updated
- Don't check microcode versions when running on hypervisors as they
are considered as lying anyway.
- Fix the 32bit objtool build and a coment typo"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/kprobes: Fix kernel crash when probing .entry_trampoline code
x86/pti: Fix a comment typo
x86/microcode: Synchronize late microcode loading
x86/microcode: Request microcode on the BSP
x86/microcode/intel: Look into the patch cache first
x86/microcode: Do not upload microcode if CPUs are offline
x86/microcode/intel: Writeback and invalidate caches before updating microcode
x86/microcode/intel: Check microcode revision before updating sibling threads
x86/microcode: Get rid of struct apply_microcode_ctx
x86/spectre_v2: Don't check microcode versions when running under hypervisors
x86/vsyscall/64: Drop "native" vsyscalls
x86/entry/64/compat: Save one instruction in entry_INT80_compat()
x86/entry: Do not special-case clone(2) in compat entry
x86/syscalls: Use COMPAT_SYSCALL_DEFINEx() macros for x86-only compat syscalls
x86/syscalls: Use proper syscall definition for sys_ioperm()
x86/entry: Remove stale syscall prototype
x86/syscalls/32: Simplify $entry == $compat entries
objtool: Fix 32-bit build
Pull RAS fixes from Thomas Gleixner:
"Two small fixes for RAS/MCE:
- Serialize sysfs changes to avoid concurrent modificaiton of
underlying data
- Add microcode revision to Machine Check records. This should have
been there forever, but now with the broken microcode versions in
the wild it has become important"
* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/MCE: Serialize sysfs changes
x86/MCE: Save microcode revision in machine check records
Pull perf updates from Thomas Gleixner:
"Another set of perf updates:
- Fix a Skylake Uncore event format declaration
- Prevent perf pipe mode from crahsing which was caused by a missing
buffer allocation
- Make the perf top popup message which tells the user that it uses
fallback mode on older kernels a debug message.
- Make perf context rescheduling work correcctly
- Robustify the jump error drawing in perf browser mode so it does
not try to create references to NULL initialized offset entries
- Make trigger_on() robust so it does not enable the trigger before
everything is set up correctly to handle it
- Make perf auxtrace respect the --no-itrace option so it does not
try to queue AUX data for decoding.
- Prevent having different number of field separators in CVS output
lines when a counter is not supported.
- Make the perf kallsyms man page usage behave like it does for all
other perf commands.
- Synchronize the kernel headers"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix ctx_event_type in ctx_resched()
perf tools: Fix trigger class trigger_on()
perf auxtrace: Prevent decoding when --no-itrace
perf stat: Fix CVS output format for non-supported counters
tools headers: Sync x86's cpufeatures.h
tools headers: Sync copy of kvm UAPI headers
perf record: Fix crash in pipe mode
perf annotate browser: Be more robust when drawing jump arrows
perf top: Fix annoying fallback message on older kernels
perf kallsyms: Fix the usage on the man page
perf/x86/intel/uncore: Fix Skylake UPI event format
Disable the kprobe probing of the entry trampoline:
.entry_trampoline is a code area that is used to ensure page table
isolation between userspace and kernelspace.
At the beginning of the execution of the trampoline, we load the
kernel's CR3 register. This has the effect of enabling the translation
of the kernel virtual addresses to physical addresses. Before this
happens most kernel addresses can not be translated because the running
process' CR3 is still used.
If a kprobe is placed on the trampoline code before that change of the
CR3 register happens the kernel crashes because int3 handling pages are
not accessible.
To fix this, add the .entry_trampoline section to the kprobe blacklist
to prohibit the probing of code before all the kernel pages are
accessible.
Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: mathieu.desnoyers@efficios.com
Cc: mhiramat@kernel.org
Link: http://lkml.kernel.org/r/1520565492-4637-2-git-send-email-francis.deslauriers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Don't populate the const read-only array 'buf' on the stack but instead
make it static. Makes the object code smaller by 64 bytes:
Before:
text data bss dec hex filename
9264 1 16 9281 2441 arch/x86/boot/compressed/eboot.o
After:
text data bss dec hex filename
9200 1 16 9217 2401 arch/x86/boot/compressed/eboot.o
(GCC version 7.2.0 x86_64)
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180308080020.22828-13-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
efi_query_variable_store() does an atomic kzalloc() unnecessarily,
because we can never get this far when called in an atomic context,
namely when nonblocking == 1.
Replace it with GFP_KERNEL.
This was found by the DCNS static analysis tool written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180308080020.22828-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Userspace RDPMC cannot possibly work for large PEBS, which was introduced in:
b8241d20699e ("perf/x86/intel: Implement batched PEBS interrupt handling (large PEBS interrupt threshold)")
When the PEBS interrupt threshold is larger than one, there is no way
to get exact auto-reload times and value for userspace RDPMC. Disable
the userspace RDPMC usage when large PEBS is enabled.
The only exception is when the PEBS interrupt threshold is 1, in which
case user-space RDPMC works well even with auto-reload events.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Fixes: b8241d20699e ("perf/x86/intel: Implement batched PEBS interrupt handling (large PEBS interrupt threshold)")
Link: http://lkml.kernel.org/r/1518474035-21006-6-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is no way to get exact auto-reload times and values which are needed
for event updates unless we flush the PEBS buffer.
Introduce intel_pmu_auto_reload_read() to drain the PEBS buffer for
auto reload event. To prevent races with the hardware, we can only
call drain_pebs() when the PMU is disabled.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Link: http://lkml.kernel.org/r/1518474035-21006-4-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is a bug when reading event->count with large PEBS enabled.
Here is an example:
# ./read_count
0x71f0
0x122c0
0x1000000001c54
0x100000001257d
0x200000000bdc5
In fixed period mode, the auto-reload mechanism could be enabled for
PEBS events, but the calculation of event->count does not take the
auto-reload values into account.
Anyone who reads event->count will get the wrong result, e.g x86_pmu_read().
This bug was introduced with the auto-reload mechanism enabled since
commit:
851559e35fd5 ("perf/x86/intel: Use the PEBS auto reload mechanism when possible")
Introduce intel_pmu_save_and_restart_reload() to calculate the
event->count only for auto-reload.
Since the counter increments a negative counter value and overflows on
the sign switch, giving the interval:
[-period, 0]
the difference between two consequtive reads is:
A) value2 - value1;
when no overflows have happened in between,
B) (0 - value1) + (value2 - (-period));
when one overflow happened in between,
C) (0 - value1) + (n - 1) * (period) + (value2 - (-period));
when @n overflows happened in between.
Here A) is the obvious difference, B) is the extension to the discrete
interval, where the first term is to the top of the interval and the
second term is from the bottom of the next interval and C) the extension
to multiple intervals, where the middle term is the whole intervals
covered.
The equation for all cases is:
value2 - value1 + n * period
Previously the event->count is updated right before the sample output.
But for case A, there is no PEBS record ready. It needs to be specially
handled.
Remove the auto-reload code from x86_perf_event_set_period() since
we'll not longer call that function in this case.
Based-on-code-from: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Fixes: 851559e35fd5 ("perf/x86/intel: Use the PEBS auto reload mechanism when possible")
Link: http://lkml.kernel.org/r/1518474035-21006-2-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The PMU is disabled in intel_pmu_handle_irq(), but cpuc->enabled is not updated
accordingly.
This is fine in current usage because no-one checks it - but fix it
for future code: for example, the drain_pebs() will be modified to
fix an auto-reload bug.
Properly save/restore the old PMU state.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: kernel test robot <fengguang.wu@intel.com>
Link: http://lkml.kernel.org/r/6f44ee84-56f8-79f1-559b-08e371eaeb78@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Large fixed period values could be truncated on Broadwell, for example:
perf record -e cycles -c 10000000000
Here the fixed period is 0x2540BE400, but the period which finally applied is
0x540BE400 - which is wrong.
The reason is that x86_pmu::limit_period() uses an u32 parameter, so the
high 32 bits of 'period' get truncated.
This bug was introduced in:
commit 294fe0f52a44 ("perf/x86/intel: Add INST_RETIRED.ALL workarounds")
It's safe to use u64 instead of u32:
- Although the 'left' is s64, the value of 'left' must be positive when
calling limit_period().
- bdw_limit_period() only modifies the lowest 6 bits, it doesn't touch
the higher 32 bits.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 294fe0f52a44 ("perf/x86/intel: Add INST_RETIRED.ALL workarounds")
Link: http://lkml.kernel.org/r/1519926894-3520-1-git-send-email-kan.liang@linux.intel.com
[ Rewrote unacceptably bad changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
According to Intel SDM 26.2.1.1, the following rules should be enforced
on vmentry:
* If the "NMI exiting" VM-execution control is 0, "Virtual NMIs"
VM-execution control must be 0.
* If the “virtual NMIs” VM-execution control is 0, the “NMI-window
exiting” VM-execution control must be 0.
This patch enforces these rules when entering an L2 guest.
Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The struct is part of the uapi, document that fact and all fields properly
and fix formatting.
No functional changes.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20180306142143.19990-3-bp@alien8.de
The check_interval file in
/sys/devices/system/machinecheck/machinecheck<cpu number>
directory is a global timer value for MCE polling. If it is changed by one
CPU, mce_restart() broadcasts the event to other CPUs to delete and restart
the MCE polling timer and __mcheck_cpu_init_timer() reinitializes the
mce_timer variable.
If more than one CPU writes a specific value to the check_interval file
concurrently, mce_timer is not protected from such concurrent accesses and
all kinds of explosions happen. Since only root can write to those sysfs
variables, the issue is not a big deal security-wise.
However, concurrent writes to these configuration variables is void of
reason so the proper thing to do is to serialize the access with a mutex.
Boris:
- Make store_int_with_restart() use device_store_ulong() to filter out
negative intervals
- Limit min interval to 1 second
- Correct locking
- Massage commit message
Signed-off-by: Seunghun Han <kkamagui@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180302202706.9434-1-kkamagui@gmail.com
Updating microcode used to be relatively rare. Now that it has become
more common we should save the microcode version in a machine check
record to make sure that those people looking at the error have this
important information bundled with the rest of the logged information.
[ Borislav: Simplify a bit. ]
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Yazen Ghannam <yazen.ghannam@amd.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180301233449.24311-1-tony.luck@intel.com
