iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mm/hwpoison: avoid the impact of hwpoison_filter() return value on mce handler

Browse Source 
When the hwpoison page meets the filter conditions, it should not be
regarded as successful memory_failure() processing for mce handler, but
should return a distinct value, otherwise mce handler regards the error
page has been identified and isolated, which may lead to calling
set_mce_nospec() to change page attribute, etc.

Here memory_failure() return -EOPNOTSUPP to indicate that the error
event is filtered, mce handler should not take any action for this
situation and hwpoison injector should treat as correct.

Link: https://lkml.kernel.org/r/20220223082135.2769649-1-luofei@unicloud.com
Signed-off-by: luofei <luofei@unicloud.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
luofei 2022-03-22 14:44:38 -07:00 committed by Linus Torvalds
parent a581865ecd
commit d1fe111fb6
5 changed files with 18 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
arch/x86/kernel/cpu/mce/core.c
View File

@ -1304,10 +1304,12 @@ static void kill_me_maybe(struct callback_head *cb)
/*
* -EHWPOISON from memory_failure() means that it already sent SIGBUS
* to the current process with the proper error info, so no need to
* send SIGBUS here again.
* to the current process with the proper error info,
* -EOPNOTSUPP means hwpoison_filter() filtered the error event,
*
* In both cases, no further processing is required.
*/
if (ret == -EHWPOISON)
if (ret == -EHWPOISON || ret == -EOPNOTSUPP)
return;
pr_err("Memory error not recovered");

2
drivers/base/memory.c
View File

@ -555,6 +555,8 @@ static ssize_t hard_offline_page_store(struct device *dev,
return -EINVAL;
pfn >>= PAGE_SHIFT;
ret = memory_failure(pfn, 0);
if (ret == -EOPNOTSUPP)
ret = 0;
return ret ? ret : count;
}

3
mm/hwpoison-inject.c
View File

@ -48,7 +48,8 @@ static int hwpoison_inject(void *data, u64 val)
inject:
pr_info("Injecting memory failure at pfn %#lx\n", pfn);
return memory_failure(pfn, 0);
err = memory_failure(pfn, 0);
return (err == -EOPNOTSUPP) ? 0 : err;
}
static int hwpoison_unpoison(void *data, u64 val)

2
mm/madvise.c
View File

@ -1067,6 +1067,8 @@ static int madvise_inject_error(int behavior,
pr_info("Injecting memory failure for pfn %#lx at process virtual address %#lx\n",
pfn, start);
ret = memory_failure(pfn, MF_COUNT_INCREASED);
if (ret == -EOPNOTSUPP)
ret = 0;
}
if (ret)

9
mm/memory-failure.c
View File

@ -1515,7 +1515,7 @@ static int memory_failure_hugetlb(unsigned long pfn, int flags)
if (TestClearPageHWPoison(head))
num_poisoned_pages_dec();
unlock_page(head);
return 0;
return -EOPNOTSUPP;
}
unlock_page(head);
res = MF_FAILED;
@ -1602,7 +1602,7 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags,
goto out;
if (hwpoison_filter(page)) {
rc = 0;
rc = -EOPNOTSUPP;
goto unlock;
}
@ -1671,6 +1671,10 @@ static DEFINE_MUTEX(mf_mutex);
*
* Must run in process context (e.g. a work queue) with interrupts
* enabled and no spinlocks hold.
*
* Return: 0 for successfully handled the memory error,
* -EOPNOTSUPP for memory_filter() filtered the error event,
* < 0(except -EOPNOTSUPP) on failure.
*/
int memory_failure(unsigned long pfn, int flags)
{
@ -1836,6 +1840,7 @@ try_again:
num_poisoned_pages_dec();
unlock_page(p);
put_page(p);
res = -EOPNOTSUPP;
goto unlock_mutex;
}