On Wed, 2015-09-16 at 21:54 -0400, Steven Rostedt wrote: > On Wed, 16 Sep 2015 22:01:06 +0200 (CEST) > Thomas Gleixner <t...@linutronix.de> wrote: > > > On Wed, 16 Sep 2015, Scott Wood wrote: > > > > > On Wed, 2015-09-16 at 18:23 +0200, Thomas Gleixner wrote: > > > > With this commit applied, my MPC5200 board fails to boot 4.3-rc1. The > > > > boot failure is silent. > > > > > > > > Bisection pointed straight to this commit. Reverting it on top of > > > > 4.3-rc1 works like a charm. > > > > > > Yes, we've been iterating on a fix for this, and I think the patches > > > posted > > > earlier today are ready to go in: > > > > > > http://patchwork.ozlabs.org/patch/518321/ > > > http://patchwork.ozlabs.org/patch/518323/ > > > > Tested-by: Thomas Gleixner <t...@linutronix.de> > > > > So now I have to chase down that one: > > > > [ 0.230210] ftrace: allocating 16560 entries in 49 pages > > [ 0.273313] ------------[ cut here ]------------ > > [ 0.278048] WARNING: at > > /home/tglx/work/kernel/tip/tip/kernel/trace/ftrace.c:1974 > > OK, so this is where ftrace converts the mcount to nops. > > Just to be clear, there's nothing in the command line that enables any > function tracing, is there? > > > [ 0.285653] Modules linked in: > > [ 0.288781] CPU: 0 PID: 0 Comm: swapper Not tainted > > 4.2.0-50528-gfac33bf-dirty #29 > > [ 0.296485] task: c06563e0 ti: c06a2000 task.ti: c06a2000 > > [ 0.301976] NIP: c008df9c LR: c008e440 CTR: 00000000 > > [ 0.307027] REGS: c06a3e80 TRAP: 0700 Not tainted > > (4.2.0-50528-gfac33bf-dirty) > > [ 0.314631] MSR: 00021032 <ME,IR,DR,RI> CR: 22028022 XER: 00000000 > > [ 0.321126] > > GPR00: 00000001 c06a3f30 c06563e0 ffffffea c3888c88 00000004 c06a3ef8 > > 764d9364 > > GPR08: 00407584 c069df92 00000000 00000001 22022028 ffffffff 03fb9000 > > 007fff00 > > GPR16: c065debc 00009032 c06b8aa0 c0011184 00000000 c06a711c 00000bb6 > > c38021a0 > > GPR24: 00000000 00008c88 00000bb6 c06a7120 c3888c88 101d6120 c3888c88 > > c00e1f2c > > [ 0.351444] NIP [c008df9c] ftrace_bug+0xbc/0x2d4 > > [ 0.356160] LR [c008e440] ftrace_process_locs+0x28c/0x6cc > > [ 0.361652] Call Trace: > > [ 0.364169] [c06a3f30] [c00971a0] buffer_ftrace_now.isra.50+0x28/0x64 > > (unreliable) > > [ 0.371888] [c06a3f60] [c008e440] ftrace_process_locs+0x28c/0x6cc > > [ 0.378119] [c06a3fb0] [c0610848] ftrace_init+0xac/0x14c > > [ 0.383559] [c06a3fc0] [c06051fc] start_kernel+0x390/0x3a8 > > [ 0.389147] [c06a3ff0] [00003438] 0x3438 > > [ 0.393136] Instruction dump: > > [ 0.396154] 483f9951 3c60c059 7fe4fb78 3863b768 7fe5fb78 483f993d > > 41b20214 48000144 > > [ 0.404060] 3d20c06a 3929df92 88090002 68000001 <0f000000> 2f800000 > > 409e01b4 3d20c06a > > [ 0.412203] ---[ end trace dc8fa200cb88537f ]--- > > [ 0.416912] ftrace failed to modify [<c00e1f2c>] > > change_protection+0x8/0x2c > > [ 0.424015] actual: 74:66:74:70 > > [ 0.427324] ftrace record flags: 0 > > [ 0.430785] (0) expected tramp: c0011198 > > > > Happens somewhere between the powerpc merge and rc1. System boots up > > to userspace and then locks hard .... > > This could be a symptom and not the problem. What the above shows is > that ftrace tried to convert the mcount at change_protection but what > it expected was there wasn't. Unfortunately, it doesn't state exactly > what it wants (that would take a arch specific function to do that, and > this is in generic code). But what it found was "74 66 74 70", which I > have no idea what type of command that is.
This is big endian, so I think that's: andis. r6,r3,29808 Which is feasible. Can you objdump the vmlinux? Mine looks like: c0157cf0 <change_protection>: c0157cf0: 7c 08 02 a6 mflr r0 c0157cf4: 90 01 00 04 stw r0,4(r1) c0157cf8: 4b eb 9b f9 bl c00118f0 <_mcount> c0157d00: 7c 08 02 a6 mflr r0 c0157d04: 7d 80 00 26 mfcr r12 c0157d08: 90 01 00 64 stw r0,100(r1) c0157d0c: bd c1 00 18 stmw r14,24(r1) c0157d10: 91 81 00 14 stw r12,20(r1) c0157d14: 81 23 00 28 lwz r9,40(r3) c0157d18: 75 2a 00 40 andis. r10,r9,64 cheers _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
