The patch titled
Subject: mm, hwpoison: when copy-on-write hits poison, take page offline
has been added to the -mm mm-unstable branch. Its filename is
mm-hwpoison-when-copy-on-write-hits-poison-take-page-offline.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-hwpoison-when-copy-on-write-hits-poison-take-page-offline.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Tony Luck <tony.luck@xxxxxxxxx>
Subject: mm, hwpoison: when copy-on-write hits poison, take page offline
Date: Fri, 21 Oct 2022 13:01:20 -0700
Cannot call memory_failure() directly from the fault handler because
mmap_lock (and others) are held.
It is important, but not urgent, to mark the source page as h/w poisoned
and unmap it from other tasks.
Use memory_failure_queue() to request a call to memory_failure() for the
page with the error.
Also provide a stub version for CONFIG_MEMORY_FAILURE=n
Link: https://lkml.kernel.org/r/20221021200120.175753-3-tony.luck@xxxxxxxxx
Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/include/linux/mm.h~mm-hwpoison-when-copy-on-write-hits-poison-take-page-offline
+++ a/include/linux/mm.h
@@ -3228,7 +3228,6 @@ enum mf_flags {
int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index,
unsigned long count, int mf_flags);
extern int memory_failure(unsigned long pfn, int flags);
-extern void memory_failure_queue(unsigned long pfn, int flags);
extern void memory_failure_queue_kick(int cpu);
extern int unpoison_memory(unsigned long pfn);
extern int sysctl_memory_failure_early_kill;
@@ -3237,11 +3236,16 @@ extern void shake_page(struct page *p);
extern atomic_long_t num_poisoned_pages __read_mostly;
extern int soft_offline_page(unsigned long pfn, int flags);
#ifdef CONFIG_MEMORY_FAILURE
+extern void memory_failure_queue(unsigned long pfn, int flags);
extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared);
void num_poisoned_pages_inc(unsigned long pfn);
void num_poisoned_pages_sub(unsigned long pfn, long i);
#else
+static inline void memory_failure_queue(unsigned long pfn, int flags)
+{
+}
+
static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared)
{
--- a/mm/memory.c~mm-hwpoison-when-copy-on-write-hits-poison-take-page-offline
+++ a/mm/memory.c
@@ -2817,8 +2817,10 @@ static inline int __wp_page_copy_user(st
unsigned long addr = vmf->address;
if (likely(src)) {
- if (copy_mc_user_highpage(dst, src, addr, vma))
+ if (copy_mc_user_highpage(dst, src, addr, vma)) {
+ memory_failure_queue(page_to_pfn(src), 0);
return -EHWPOISON;
+ }
return 0;
}
_
Patches currently in -mm which might be from tony.luck@xxxxxxxxx are
mm-hwpoison-try-to-recover-from-copy-on-write-faults.patch
mm-hwpoison-when-copy-on-write-hits-poison-take-page-offline.patch
