Only unmap the page when the memory error is properly handled by calling memory_failure(), not the other way around.
Fixes: 26f8c38bb466("x86/mm, mm/hwpoison: Don't unconditionally unmap kernel 1:1 pages")
Signed-off-by: luofei luofei@unicloud.com Cc: stable@vger.kernel.org #v4.14 --- arch/x86/kernel/cpu/mcheck/mce.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 95c09db1bba2..d8399a689165 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -589,7 +589,7 @@ static int srao_decode_notifier(struct notifier_block *nb, unsigned long val,
if (mce_usable_address(mce) && (mce->severity == MCE_AO_SEVERITY)) { pfn = mce->addr >> PAGE_SHIFT; - if (memory_failure(pfn, MCE_VECTOR, 0)) + if (!memory_failure(pfn, MCE_VECTOR, 0)) mce_unmap_kpfn(pfn); }
On Mon, Feb 07, 2022 at 02:52:42AM -0500, luofei wrote:
Only unmap the page when the memory error is properly handled by calling memory_failure(), not the other way around.
Fixes: 26f8c38bb466("x86/mm, mm/hwpoison: Don't unconditionally unmap kernel 1:1 pages")
This commit is not in Linus's tree. Please use the correct commit id.
thanks,
greg k-h
On Mon, Feb 07, 2022 at 09:14:23AM +0100, Greg KH wrote:
On Mon, Feb 07, 2022 at 02:52:42AM -0500, luofei wrote:
Only unmap the page when the memory error is properly handled by calling memory_failure(), not the other way around.
Fixes: 26f8c38bb466("x86/mm, mm/hwpoison: Don't unconditionally unmap kernel 1:1 pages")
This commit is not in Linus's tree. Please use the correct commit id.
I think he's trying to fix the backport:
see 26f8c38bb466c1a2d232d7609fb4bfb4bc121678 which is the stable tree backport:
@@ -582,7 +586,8 @@ static int srao_decode_notifier(struct notifier_block *nb, unsigned long val,
if (mce_usable_address(mce) && (mce->severity == MCE_AO_SEVERITY)) { pfn = mce->addr >> PAGE_SHIFT; - memory_failure(pfn, MCE_VECTOR, 0); + if (memory_failure(pfn, MCE_VECTOR, 0)) + mce_unmap_kpfn(pfn); }
vs the upstream commit:
fd0e786d9d09024f67bd71ec094b110237dc3840
@@ -590,7 +594,8 @@ static int srao_decode_notifier(struct notifier_block *nb, unsigned long val,
if (mce_usable_address(mce) && (mce->severity == MCE_AO_SEVERITY)) { pfn = mce->addr >> PAGE_SHIFT; - memory_failure(pfn, 0); + if (!memory_failure(pfn, 0)) + mce_unmap_kpfn(pfn); }
return NOTIFY_OK;
On Mon, Feb 07, 2022 at 10:35:41AM +0100, Borislav Petkov wrote:
On Mon, Feb 07, 2022 at 09:14:23AM +0100, Greg KH wrote:
On Mon, Feb 07, 2022 at 02:52:42AM -0500, luofei wrote:
Only unmap the page when the memory error is properly handled by calling memory_failure(), not the other way around.
Fixes: 26f8c38bb466("x86/mm, mm/hwpoison: Don't unconditionally unmap kernel 1:1 pages")
This commit is not in Linus's tree. Please use the correct commit id.
I think he's trying to fix the backport:
see 26f8c38bb466c1a2d232d7609fb4bfb4bc121678 which is the stable tree backport:
@@ -582,7 +586,8 @@ static int srao_decode_notifier(struct notifier_block *nb, unsigned long val, if (mce_usable_address(mce) && (mce->severity == MCE_AO_SEVERITY)) { pfn = mce->addr >> PAGE_SHIFT;
memory_failure(pfn, MCE_VECTOR, 0);
if (memory_failure(pfn, MCE_VECTOR, 0))mce_unmap_kpfn(pfn); }vs the upstream commit:
fd0e786d9d09024f67bd71ec094b110237dc3840
@@ -590,7 +594,8 @@ static int srao_decode_notifier(struct notifier_block *nb, unsigned long val, if (mce_usable_address(mce) && (mce->severity == MCE_AO_SEVERITY)) { pfn = mce->addr >> PAGE_SHIFT;
memory_failure(pfn, 0);
if (!memory_failure(pfn, 0))mce_unmap_kpfn(pfn); }return NOTIFY_OK;
Ah, ok, if so, this needs to be documented really really well in the changelog text so no one is confused. Like me :)
thanks,
greg k-h
linux-stable-mirror@lists.linaro.org
-
Borislav Petkov -
Greg KH -
luofei