From mboxrd@z Thu Jan 1 00:00:00 1970 From: Suresh Siddha Subject: Re: [2.6.27-rc2-git4] Kernel panic on VIA Ester+VIA CX700 Date: Mon, 11 Aug 2008 11:17:52 -0700 Message-ID: <20080811181752.GK13158@linux-os.sc.intel.com> References: <20080809220154.GO28946@ZenIV.linux.org.uk> <20080810133056.2fd69a20@neptune.home> <489F7C2B.30807@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <489F7C2B.30807@zytor.com> Sender: linux-ide-owner@vger.kernel.org To: "H. Peter Anvin" Cc: Bruno =?iso-8859-1?Q?Pr=E9mont?= , Herbert Xu , Al Viro , "Rafael J. Wysocki" , "linux-kernel@vger.kernel.org" , "linux-scsi@vger.kernel.org" , "linux-ide@vger.kernel.org" , "Siddha, Suresh B" , Ingo Molnar , Wolfgang Walter List-Id: linux-scsi@vger.kernel.org On Sun, Aug 10, 2008 at 04:39:23PM -0700, H. Peter Anvin wrote: > Bruno Pr=E9mont wrote: > > > > Recompiling without viafb+squashfs patches makes the panic go away. > > > > So something from viafb or squashfs triggers the panic or prepare > > for something else to trigger it... > > >=20 > Out of those, viafb by far seems most likely. Could you try compilin= g > with only one or the other? [ 5.010629] general protection fault: 0000 [#1]=20 [ 5.021782] Modules linked in: [ 5.030227]=20 [ 5.030227] Pid: 3, comm: ksoftirqd/0 Not tainted (2.6.27-rc2-git4_n= ocrypto #1) [ 5.030227] EIP: 0060:[] EFLAGS: 00010046 CPU: 0 [ 5.030227] EIP is at math_state_restore+0x25/0x60 [ 5.030227] EAX: f781db3d EBX: f781d898 ECX: 00000000 EDX: 00000000 [ 5.030227] ESI: f781d000 EDI: f782c20c EBP: f781d840 ESP: f781d838 [ 5.030227] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 [ 5.030227] Process ksoftirqd/0 (pid: 3, ti=3Df781d000 task=3Df782c6= a0 task.ti=3Df782a000) [ 5.030227] Stack: f782c000 f782c6a0 f781d890 c01038dd f782c000 0000= 0000 f782c000 f782c6a0=20 [ 5.030227] f782c20c f781d890 f7807e00 0000007b 0000007b 0000= 0000 ffffffff c0101e8f=20 [ 5.030227] 00000060 00010002 f782c8ac f782c000 c04d8180 c011= fa50 f782afc0 c03cfa61=20 [ 5.030227] Call Trace: [ 5.030227] [] ? device_not_available+0x2d/0x32 [ 5.030227] [] ? __switch_to+0x2f/0x130 It got a GP fault, because in __switch_to() we were doing unlazy_fpu() = and fxsave generated a DNA fault(which shouldn't happen unless we are hitti= ng the via padlock instruction issue or something else) and the math_state_res= tore() found the task's math state pointer to be 0xf781db3d (EAX in the oops) = and while doing fxrstor we got GP fault, as the fxrstor pointer(EAX) is not 16byt= e aligned. It is interesting to see the EAX value similar to stack pointer. Task's =46P area gets dynamically allocated and as such EAX def looks wrong he= re. I also see the config is using 4K stacks. Some config(viafb/squashfs?) = causing some thing wrong with the kernel stack?