Jiri Slaby <jslaby@xxxxxxx> wrote: > On 04/13/2012 10:02 AM, Jiri Slaby wrote: > > On 04/13/2012 04:30 AM, Michael Neuling wrote: > >> Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote: > >> > >>> Hi all, > >>> > >>> Some (not all) of my PowerPC boot tests have failed like this after > >>> getting into user mode (this one was just after udev started, but others > >>> are after other processes getting going): > >>> > >>> Unable to handle kernel paging request for data at address 0xc0000003f9d550 > >>> Faulting instruction address: 0xc0000000001b7f40 > >>> Oops: Kernel access of bad area, sig: 11 [#1] > >>> SMP NR_CPUS=32 NUMA pSeries > >>> Modules linked in: ehea > >>> NIP: c0000000001b7f40 LR: c0000000001b7f14 CTR: c0000000000e04f0 > >>> REGS: c0000003f68bf6b0 TRAP: 0300 Not tainted (3.4.0-rc2-autokern1) > >>> MSR: 800000000280b032 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI> CR: 24422424 XER: 20000001 > >>> SOFTE: 1 > >>> CFAR: 000000000000562c > >>> DAR: 00c0000003f9d550, DSISR: 40000000 > >>> TASK = c0000003f8818000[3192] 'kdump' THREAD: c0000003f68bc000 CPU: 5 > >>> GPR00: 0000000000000000 c0000003f68bf930 c000000000ce1d40 c0000003fe00ec00 > >>> GPR04: 00000000000002d0 0000000000000038 c0000003f8f935e8 c000000000e55280 > >>> GPR08: 0000000000000011 c000000000bcb280 c000000000bcb1e8 000000000028a000 > >>> GPR12: 0000000024422424 c00000000f33bc80 00000fffdd90a770 0000000000081000 > >>> GPR16: c0000003f846c000 000000000de4f7a0 f00000000de4f7a0 0000000000000000 > >>> GPR20: c0000003f8365408 c0000003f8365480 c0000003f8e5d110 0000000000000000 > >>> GPR24: 0000000000000100 c0000003f8365400 c0000000001e5424 00000000000002d0 > >>> GPR28: 0000000000000800 00c0000003f9d550 c000000000c5b718 c0000003fe00ec00 > >>> NIP [c0000000001b7f40] .__kmalloc+0x70/0x230 > >>> LR [c0000000001b7f14] .__kmalloc+0x44/0x230 > >>> Call Trace: > >>> [c0000003f68bf930] [c0000003f68bf9b0] 0xc0000003f68bf9b0 (unreliable) > >>> [c0000003f68bf9e0] [c0000000001e5424] .alloc_fdmem+0x24/0x70 > >>> [c0000003f68bfa60] [c0000000001e54f8] .alloc_fdtable+0x88/0x130 > >>> [c0000003f68bfaf0] [c0000000001e5924] .dup_fd+0x384/0x450 > >>> [c0000003f68bfbd0] [c00000000009a310] .copy_process+0x880/0x11d0 > >>> [c0000003f68bfcd0] [c00000000009aee0] .do_fork+0x70/0x400 > >>> [c0000003f68bfdc0] [c0000000000141c4] .sys_clone+0x54/0x70 > >>> [c0000003f68bfe30] [c000000000009aa0] .ppc_clone+0x8/0xc > >>> Instruction dump: > >>> 4bff9281 2ba30010 7c7f1b78 40dd00f4 e96d0040 e93f0000 7ce95a14 e9070008 > >>> 7fa9582a 2fbd0000 41de0054 e81f0022 <7f3d002a> 38000000 886d01f2 980d01f2 > >>> ---[ end trace 366fe6c7ced3bfb0 ]--- > >>> > >>> This did not happen yesterday. Just wondering if anyone can think of > >>> anything obvious. Full console log at > >>> http://ozlabs.org/~sfr/next-20120411.log.bz2 > >> > >> I managed to bisect this down using pseries_defconfig with next-20120412 > >> to this patch: > >> > >> commit 85bbc003b24335e253a392f6a9874103b77abb36 > >> Author: Jiri Slaby <jslaby@xxxxxxx> > >> Date: Mon Apr 2 13:54:22 2012 +0200 > >> > >> TTY: HVC, use tty from tty_port > >> > >> The driver already used refcounting. So we just switch it to tty_port > >> helpers. And switch to tty_port->lock for tty. > >> > >> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> > >> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx > >> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > >> > >> Reverting this commit (and 0146b6939074ebe14ece3604fd00e7be128a3812 > >> otherwise git barfs) fixes the problem on next-20120412. > >> > >> I'm assuming we got the ref count changes wrong somewhere in the patch > >> but the tty code is beyond me. Jiri, can you take a look? > > > > Yeah, I see. I forgot to remove a couple of tty reference drops. The > > reference is dropped by tty_port_tty_set in open/close/hangup now. Does > > the attached patch help? > > And the patch is incomplete. Now we have a leak. This one should work. Fixes the problem here.. Thanks. Tested-by: Michael Neuling <mikey@xxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
