----- Original Message ----- > From: "Dave Chinner" <david@xxxxxxxxxxxxx> > To: "CAI Qian" <caiqian@xxxxxxxxxx> > Cc: "LKML" <linux-kernel@xxxxxxxxxxxxxxx>, stable@xxxxxxxxxxxxxxx, xfs@xxxxxxxxxxx > Sent: Thursday, May 23, 2013 11:46:11 AM > Subject: Re: 3.9.2: xfstests triggered panic > > On Wed, May 22, 2013 at 11:16:56PM -0400, CAI Qian wrote: > > ----- Original Message ----- > > > From: "Dave Chinner" <david@xxxxxxxxxxxxx> > > > To: "CAI Qian" <caiqian@xxxxxxxxxx> > > > Cc: "LKML" <linux-kernel@xxxxxxxxxxxxxxx>, stable@xxxxxxxxxxxxxxx, > > > xfs@xxxxxxxxxxx > > > Sent: Wednesday, May 22, 2013 5:53:00 PM > > > Subject: Re: 3.9.2: xfstests triggered panic > > > > > > On Wed, May 22, 2013 at 04:39:58AM -0400, CAI Qian wrote: > > > > Reproduced on almost all s390x guests by running xfstests. > > > > > > > > 14634.396658¨ XFS (dm-1): Mounting Filesystem > > > > 14634.525522¨ XFS (dm-1): Ending clean mount > > > > 14640.413007¨ <000000000017c6d4>¨ idle_balance+0x1a0/0x340 > > > > 14640.413010¨ <000000000063303e>¨ __schedule+0xa22/0xaf0 > > > > 14640.428279¨ <0000000000630da6>¨ schedule_timeout+0x186/0x2c0 > > > > 14640.428289¨ <00000000001cf864>¨ rcu_gp_kthread+0x1bc/0x298 > > > > 14640.428300¨ <0000000000158c5a>¨ kthread+0xe6/0xec > > > > 14640.428304¨ <0000000000634de6>¨ kernel_thread_starter+0x6/0xc > > > > 14640.428308¨ <0000000000634de0>¨ kernel_thread_starter+0x0/0xc > > > > 14640.428311¨ Last Breaking-Event-Address: > > > > 14640.428314¨ <000000000016bd76>¨ walk_tg_tree_from+0x3a/0xf4 > > > > 14640.428319¨ list_add corruption. next->prev should be prev > > > > (0000000000000918 > > > > ), but was (null). (next= (null)). > > > > > > Where's XFS in this? walk_tg_tree_from() is part of the scheduler > > > code. This kind of implies a stack corruption.... > > > > > > > Sometimes, this pops up, > > > > [16907.275002] WARNING: at kernel/rcutree.c:1960 > > > > > > > > or this, > > > > 15316.154171¨ XFS (dm-1): Mounting Filesystem > > > > 15316.255796¨ XFS (dm-1): Ending clean mount > > > > 15320.364246¨ 00000000006367a2: e310b0080004 lg > > > > %r1,8(%r > > > > 11) > > > > 15320.364249¨ 00000000006367a8: 41101010 la > > > > %r1,16(% > > > > r1) > > > > 15320.364251¨ 00000000006367ac: e33010000004 lg > > > > %r3,0(%r > > > > 1) > > > > 15320.364252¨ Call Trace: > > > > 15320.364252¨ Last Breaking-Event-Address: > > > > 15320.364253¨ � <0000000000000000>¨ Kernel stack overflow. > > > > 15320.364308¨ CPU: 0 Tainted: GF W 3.9.2 #1 > > > > 15320.364309¨ Process rhts-test-runne (pid: 625, task: > > > > 000000003dccc890, > > > > ksp: 0 > > > > > > .... and there you go - a stack overflow. Your kernel stack size is > > > too small. > > > > > > I'd suggest that you need 16k stacks on s390 - IIRC every function > > > call has 128 byte stack frame, and there are call chains 70-80 > > > functions deep in the storage stack... > > Hmm, I am unsure how to set to 16k stack there > > Are you build a 64 bit s390 kernel or a 32 bit kernel? 32 bit > kernels only have an 8k stack size, 64 bit kernels are 16k (see > arch/s390/Makefile). It is 64-bit. > > $ git grep STACK_SIZE arch/s390 |head -2 > arch/s390/Makefile:STACK_SIZE := 8192 > arch/s390/Makefile:STACK_SIZE := 16384 > > As it is, the stack frame usage is worse than I thought: > > $ git grep STACK_FRAME_OVERHEAD arch/s390 |head -2 > arch/s390/include/uapi/asm/ptrace.h:#define STACK_FRAME_OVERHEAD 96 /* > size of minimum stack frame */ > arch/s390/include/uapi/asm/ptrace.h:#define STACK_FRAME_OVERHEAD 160 /* > size of minimum stack frame */ > > Overhead is 96 bytes for 32 bit and 160 bytes for 64 bit. So 16k > stack size is going to have big troubles with a 70-80 function deep > call chain. > > As for powerpc: > > arch/powerpc/include/asm/ppc_asm.h:#define STACKFRAMESIZE 256 > > Yeah, same issue. > > But, seriously, these stack traces are meaningless to anyone not > familiar with s390 or power7 - they indicate a problem detected > in the idle loop, not where ever the stack overran. > > Can you please work with the s390/power7 people to obtain whatever > stack it was that overflowed, and we can go from there. OK, I'll do. CAI Qian > > Cheers, > > Dave. > -- > Dave Chinner > david@xxxxxxxxxxxxx > -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html