| Message ID | 166153428781.2758201.1990616683438224741.stgit@dwillia2-xfh.jf.intel.com (mailing list archive) |
|---|---|
| State | Deferred, archived |
| Headers | show |
| Series | mm, xfs, dax: Fixes for memory_failure() handling | expand |
On Fri, Aug 26, 2022 at 10:18:07AM -0700, Dan Williams wrote: > Some pagemap types, like MEMORY_DEVICE_GENERIC (device-dax) do not even > have pagemap ops which results in crash signatures like this: > > BUG: kernel NULL pointer dereference, address: 0000000000000010 > #PF: supervisor read access in kernel mode > #PF: error_code(0x0000) - not-present page > PGD 8000000205073067 P4D 8000000205073067 PUD 2062b3067 PMD 0 > Oops: 0000 [#1] PREEMPT SMP PTI > CPU: 22 PID: 4535 Comm: device-dax Tainted: G OE N 6.0.0-rc2+ #59 > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 > RIP: 0010:memory_failure+0x667/0xba0 > [..] > Call Trace: > <TASK> > ? _printk+0x58/0x73 > do_madvise.part.0.cold+0xaf/0xc5 > > Check for ops before checking if the ops have a memory_failure() > handler. > > Fixes: 33a8f7f2b3a3 ("pagemap,pmem: introduce ->memory_failure()") > Cc: Shiyang Ruan <ruansy.fnst@fujitsu.com> > Cc: Christoph Hellwig <hch@lst.de> > Cc: Darrick J. Wong <djwong@kernel.org> > Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> > Cc: Al Viro <viro@zeniv.linux.org.uk> > Cc: Dave Chinner <david@fromorbit.com> > Cc: Goldwyn Rodrigues <rgoldwyn@suse.de> > Cc: Jane Chu <jane.chu@oracle.com> > Cc: Matthew Wilcox <willy@infradead.org> > Cc: Miaohe Lin <linmiaohe@huawei.com> > Cc: Ritesh Harjani <riteshh@linux.ibm.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Signed-off-by: Dan Williams <dan.j.williams@intel.com> Thank you for sending patches, this looks fine to me. Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> > --- > include/linux/memremap.h | 5 +++++ > mm/memory-failure.c | 2 +- > 2 files changed, 6 insertions(+), 1 deletion(-) > > diff --git a/include/linux/memremap.h b/include/linux/memremap.h > index 19010491a603..c3b4cc84877b 100644 > --- a/include/linux/memremap.h > +++ b/include/linux/memremap.h > @@ -139,6 +139,11 @@ struct dev_pagemap { > }; > }; > > +static inline bool pgmap_has_memory_failure(struct dev_pagemap *pgmap) > +{ > + return pgmap->ops && pgmap->ops->memory_failure; > +} > + > static inline struct vmem_altmap *pgmap_altmap(struct dev_pagemap *pgmap) > { > if (pgmap->flags & PGMAP_ALTMAP_VALID) > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 14439806b5ef..8a4294afbfa0 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1928,7 +1928,7 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, > * Call driver's implementation to handle the memory failure, otherwise > * fall back to generic handler. > */ > - if (pgmap->ops->memory_failure) { > + if (pgmap_has_memory_failure(pgmap)) { > rc = pgmap->ops->memory_failure(pgmap, pfn, 1, flags); > /* > * Fall back to generic handler too if operation is not
On 2022/8/27 1:18, Dan Williams wrote: > Some pagemap types, like MEMORY_DEVICE_GENERIC (device-dax) do not even > have pagemap ops which results in crash signatures like this: > > BUG: kernel NULL pointer dereference, address: 0000000000000010 > #PF: supervisor read access in kernel mode > #PF: error_code(0x0000) - not-present page > PGD 8000000205073067 P4D 8000000205073067 PUD 2062b3067 PMD 0 > Oops: 0000 [#1] PREEMPT SMP PTI > CPU: 22 PID: 4535 Comm: device-dax Tainted: G OE N 6.0.0-rc2+ #59 > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 > RIP: 0010:memory_failure+0x667/0xba0 > [..] > Call Trace: > <TASK> > ? _printk+0x58/0x73 > do_madvise.part.0.cold+0xaf/0xc5 > > Check for ops before checking if the ops have a memory_failure() > handler. > > Fixes: 33a8f7f2b3a3 ("pagemap,pmem: introduce ->memory_failure()") > Cc: Shiyang Ruan <ruansy.fnst@fujitsu.com> > Cc: Christoph Hellwig <hch@lst.de> > Cc: Darrick J. Wong <djwong@kernel.org> > Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> > Cc: Al Viro <viro@zeniv.linux.org.uk> > Cc: Dave Chinner <david@fromorbit.com> > Cc: Goldwyn Rodrigues <rgoldwyn@suse.de> > Cc: Jane Chu <jane.chu@oracle.com> > Cc: Matthew Wilcox <willy@infradead.org> > Cc: Miaohe Lin <linmiaohe@huawei.com> > Cc: Ritesh Harjani <riteshh@linux.ibm.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Signed-off-by: Dan Williams <dan.j.williams@intel.com> LGTM. Thanks for fixing this. Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Thanks, Miaohe Lin > --- > include/linux/memremap.h | 5 +++++ > mm/memory-failure.c | 2 +- > 2 files changed, 6 insertions(+), 1 deletion(-) > > diff --git a/include/linux/memremap.h b/include/linux/memremap.h > index 19010491a603..c3b4cc84877b 100644 > --- a/include/linux/memremap.h > +++ b/include/linux/memremap.h > @@ -139,6 +139,11 @@ struct dev_pagemap { > }; > }; > > +static inline bool pgmap_has_memory_failure(struct dev_pagemap *pgmap) > +{ > + return pgmap->ops && pgmap->ops->memory_failure; > +} > + > static inline struct vmem_altmap *pgmap_altmap(struct dev_pagemap *pgmap) > { > if (pgmap->flags & PGMAP_ALTMAP_VALID) > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 14439806b5ef..8a4294afbfa0 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1928,7 +1928,7 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, > * Call driver's implementation to handle the memory failure, otherwise > * fall back to generic handler. > */ > - if (pgmap->ops->memory_failure) { > + if (pgmap_has_memory_failure(pgmap)) { > rc = pgmap->ops->memory_failure(pgmap, pfn, 1, flags); > /* > * Fall back to generic handler too if operation is not > > > . >
Looks good:
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 19010491a603..c3b4cc84877b 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -139,6 +139,11 @@ struct dev_pagemap { }; }; +static inline bool pgmap_has_memory_failure(struct dev_pagemap *pgmap) +{ + return pgmap->ops && pgmap->ops->memory_failure; +} + static inline struct vmem_altmap *pgmap_altmap(struct dev_pagemap *pgmap) { if (pgmap->flags & PGMAP_ALTMAP_VALID) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 14439806b5ef..8a4294afbfa0 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1928,7 +1928,7 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, * Call driver's implementation to handle the memory failure, otherwise * fall back to generic handler. */ - if (pgmap->ops->memory_failure) { + if (pgmap_has_memory_failure(pgmap)) { rc = pgmap->ops->memory_failure(pgmap, pfn, 1, flags); /* * Fall back to generic handler too if operation is not
Some pagemap types, like MEMORY_DEVICE_GENERIC (device-dax) do not even have pagemap ops which results in crash signatures like this: BUG: kernel NULL pointer dereference, address: 0000000000000010 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 8000000205073067 P4D 8000000205073067 PUD 2062b3067 PMD 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 22 PID: 4535 Comm: device-dax Tainted: G OE N 6.0.0-rc2+ #59 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:memory_failure+0x667/0xba0 [..] Call Trace: <TASK> ? _printk+0x58/0x73 do_madvise.part.0.cold+0xaf/0xc5 Check for ops before checking if the ops have a memory_failure() handler. Fixes: 33a8f7f2b3a3 ("pagemap,pmem: introduce ->memory_failure()") Cc: Shiyang Ruan <ruansy.fnst@fujitsu.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Darrick J. Wong <djwong@kernel.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dave Chinner <david@fromorbit.com> Cc: Goldwyn Rodrigues <rgoldwyn@suse.de> Cc: Jane Chu <jane.chu@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Ritesh Harjani <riteshh@linux.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- include/linux/memremap.h | 5 +++++ mm/memory-failure.c | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-)