On Tue 29-05-12 08:48:00, Aneesh Kumar K.V wrote: > Michal Hocko <mhocko@xxxxxxx> writes: > > > On Mon 28-05-12 20:51:30, Aneesh Kumar K.V wrote: > >> From: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx> > >> > >> The change was introduced by "hugetlb: simplify migrate_huge_page() " > >> > >> We should use compound page head instead of tail pages in > >> migrate_huge_page(). > >> > >> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxxxxxxx> > >> --- > >> mm/memory-failure.c | 4 ++-- > >> 1 file changed, 2 insertions(+), 2 deletions(-) > >> > >> This is an important bug fix. If we want we can fold it with the not > >> yet merged upstream patch mentioned above in linux-next. The stack > >> trace for the crash is > >> > >> [ 75.337421] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 > >> [ 75.338386] IP: [<ffffffff816b3f0f>] __mutex_lock_common+0xa1/0x350 > >> [ 75.338386] PGD 1d700067 PUD 1d7dd067 PMD 0 > >> [ 75.338386] Oops: 0002 [#1] SMP > >> [ 75.338386] CPU 1 > >> [ 75.338386] Modules linked in: > >> ... > >> ... > >> > >> [ 75.338386] Call Trace: > >> [ 75.338386] [<ffffffff810ffc04>] ? try_to_unmap_file+0x38/0x51c > >> [ 75.338386] [<ffffffff810ffc04>] ? try_to_unmap_file+0x38/0x51c > >> [ 75.338386] [<ffffffff813b5f8b>] ? vsnprintf+0x83/0x421 > >> [ 75.338386] [<ffffffff816b427d>] mutex_lock_nested+0x2a/0x31 > >> [ 75.338386] [<ffffffff8110999b>] ? alloc_huge_page_node+0x1d/0x55 > >> [ 75.338386] [<ffffffff810ffc04>] try_to_unmap_file+0x38/0x51c > >> [ 75.338386] [<ffffffff8110999b>] ? alloc_huge_page_node+0x1d/0x55 > >> [ 75.338386] [<ffffffff810a06b9>] ? arch_local_irq_save+0x9/0xc > >> [ 75.338386] [<ffffffff816b5e3b>] ? _raw_spin_unlock+0x23/0x27 > >> [ 75.338386] [<ffffffff81100839>] try_to_unmap+0x25/0x3c > >> [ 75.338386] [<ffffffff810641c2>] ? console_unlock+0x210/0x238 > >> [ 75.338386] [<ffffffff811141e3>] migrate_huge_page+0x8d/0x178 > > > > This should be part of the changelog. > > I was expecting the patch to be folded back to the existing patch in > -mm. That is the reason I added stack trace in the notes section so that > if we decided to keep it as a separate patch we can pull the stack trace > and add it to commit message. OK. -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>