| Message ID | 20210325230938.30752-2-joao.m.martins@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm, sparse-vmemmap: Introduce compound pagemaps | expand |
On Thu, Mar 25, 2021 at 4:10 PM Joao Martins <joao.m.martins@oracle.com> wrote: > > memory_failure_dev_pagemap() at the moment assumes base pages (e.g. > dax_lock_page()). For pagemap with compound pages fetch the > compound_head in case we are handling a tail page memory failure. > > Currently this is a nop, but in the advent of compound pages in > dev_pagemap it allows memory_failure_dev_pagemap() to keep working. > > Reported-by: Jane Chu <jane.chu@oracle.com> > Signed-off-by: Joao Martins <joao.m.martins@oracle.com> > --- > mm/memory-failure.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 24210c9bd843..94240d772623 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1318,6 +1318,8 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, > goto out; > } > > + page = compound_head(page); Unless / until we do compound pages for the filesystem-dax case, I would add a comment like: /* pages instantiated by device-dax (not filesystem-dax) may be compound pages */
On 4/24/21 1:12 AM, Dan Williams wrote: > On Thu, Mar 25, 2021 at 4:10 PM Joao Martins <joao.m.martins@oracle.com> wrote: >> >> memory_failure_dev_pagemap() at the moment assumes base pages (e.g. >> dax_lock_page()). For pagemap with compound pages fetch the >> compound_head in case we are handling a tail page memory failure. >> >> Currently this is a nop, but in the advent of compound pages in >> dev_pagemap it allows memory_failure_dev_pagemap() to keep working. >> >> Reported-by: Jane Chu <jane.chu@oracle.com> >> Signed-off-by: Joao Martins <joao.m.martins@oracle.com> >> --- >> mm/memory-failure.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/mm/memory-failure.c b/mm/memory-failure.c >> index 24210c9bd843..94240d772623 100644 >> --- a/mm/memory-failure.c >> +++ b/mm/memory-failure.c >> @@ -1318,6 +1318,8 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, >> goto out; >> } >> >> + page = compound_head(page); > > Unless / until we do compound pages for the filesystem-dax case, I > would add a comment like: > > /* pages instantiated by device-dax (not filesystem-dax) may be > compound pages */ > I've fixed up with the comment. Thanks!
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 24210c9bd843..94240d772623 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1318,6 +1318,8 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, goto out; } + page = compound_head(page); + /* * Prevent the inode from being freed while we are interrogating * the address_space, typically this would be handled by
memory_failure_dev_pagemap() at the moment assumes base pages (e.g. dax_lock_page()). For pagemap with compound pages fetch the compound_head in case we are handling a tail page memory failure. Currently this is a nop, but in the advent of compound pages in dev_pagemap it allows memory_failure_dev_pagemap() to keep working. Reported-by: Jane Chu <jane.chu@oracle.com> Signed-off-by: Joao Martins <joao.m.martins@oracle.com> --- mm/memory-failure.c | 2 ++ 1 file changed, 2 insertions(+)