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authorluofei <luofei@unicloud.com>2022-03-22 14:44:38 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-03-22 15:57:07 -0700
commitd1fe111fb62a1cf0446a2919f5effbb33ad0702c (patch)
tree6574928df84f4ec14b01945db7c003748bf092a0
parenta581865ecd0a5a0b8464d6f1e668ae6681c1572f (diff)
downloadlinux-d1fe111fb62a1cf0446a2919f5effbb33ad0702c.tar.gz
mm/hwpoison: avoid the impact of hwpoison_filter() return value on mce handler
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>
-rw-r--r--arch/x86/kernel/cpu/mce/core.c8
-rw-r--r--drivers/base/memory.c2
-rw-r--r--mm/hwpoison-inject.c3
-rw-r--r--mm/madvise.c2
-rw-r--r--mm/memory-failure.c9
5 files changed, 18 insertions, 6 deletions
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 5818b837fd4d..05c6469db769 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -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");
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 365cd4a7f239..abf407e45467 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -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;
}
diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c
index f74552977649..bb0cea5468cb 100644
--- a/mm/hwpoison-inject.c
+++ b/mm/hwpoison-inject.c
@@ -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)
diff --git a/mm/madvise.c b/mm/madvise.c
index 38d0f515d548..7b5d6fc99a90 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -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)
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 80fc9dca4d21..f75a2ed72e69 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -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;
}