> -----Original Message----- > From: heming.zhao@xxxxxxxx [mailto:heming.zhao@xxxxxxxx] > Sent: Monday, April 12, 2021 7:40 PM > To: Sudhakar Panneerselvam <sudhakar.panneerselvam@xxxxxxxxxx>; linux-raid@xxxxxxxxxxxxxxx; song@xxxxxxxxxx > Cc: lidong.zhong@xxxxxxxx; xni@xxxxxxxxxx; colyli@xxxxxxxx; Martin Petersen <martin.petersen@xxxxxxxxxx> > Subject: Re: [PATCH] md/bitmap: wait for external bitmap writes to complete during tear down > > On 4/13/21 9:07 AM, Sudhakar Panneerselvam wrote: > > NULL pointer dereference was observed in super_written() when it tries > > to access the mddev structure. > > > > [The below stack trace is from an older kernel, but the problem described > > in this patch applies to the mainline kernel.] > > ... ... > > > > The solution is to call md_super_wait() for external bitmaps after the > > last call to md_bitmap_daemon_work() in md_bitmap_flush() to ensure there > > are no pending bitmap writes before proceeding with the tear down. > > > > Signed-off-by: Sudhakar Panneerselvam <sudhakar.panneerselvam@xxxxxxxxxx> > > Reviewed-by: Heming Zhao <heming.zhao@xxxxxxxx> > > --- > > drivers/md/md-bitmap.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > Hello Sudhakar, > > A few info to you. If I understand kernel patch submit rules correctly. > 1. > You couldn't add the line "Reviewed-by: Heming Zhao <heming.zhao@xxxxxxxx>" before > I give you this line in my email. > But take it easy, you can add my name now. > > 2. > This is v2 patch, you should change title from [PATCH] to [PATCH v2], and > also need to write changelog in patch. My apologies. Will resend the patch with the modifications Thanks Sudhakar > > Thanks, > Heming
