On Mon, Feb 10, 2014 at 11:32:23AM +0100, Thomas Gleixner wrote: > On Mon, 10 Feb 2014, Mika Westerberg wrote: > > From: Thomas Gleixner <t...@linutronix.de> > > > > If we cannot calibrate TSC via MSR based calibration > > try_msr_calibrate_tsc() stores zero to fast_calibrate and returns that to > > the caller. This value gets then propagated further to clockevents code > > resulting division by zero oops like the one below: > > > > divide error: 0000 [#1] PREEMPT SMP > > Modules linked in: > > CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 3.13.0+ #47 > > task: ffff880075508000 ti: ffff880075506000 task.ti: ffff880075506000 > > RIP: 0010:[<ffffffff810aec14>] [<ffffffff810aec14>] > > clockevents_config.part.3+0x24/0xa0 > > RSP: 0000:ffff880075507e58 EFLAGS: 00010246 > > RAX: ffffffffffffffff RBX: ffff880079c0cd80 RCX: 0000000000000000 > > RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffffffffff > > RBP: ffff880075507e70 R08: 0000000000000001 R09: 00000000000000be > > R10: 00000000000000bd R11: 0000000000000003 R12: 000000000000b008 > > R13: 0000000000000008 R14: 000000000000b010 R15: 0000000000000000 > > FS: 0000000000000000(0000) GS:ffff880079c00000(0000) > > knlGS:0000000000000000 > > CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > > CR2: ffff880079fff000 CR3: 0000000001c0b000 CR4: 00000000001006f0 > > Stack: > > ffff880079c0cd80 000000000000b008 0000000000000008 ffff880075507e88 > > ffffffff810aecb0 ffff880079c0cd80 ffff880075507e98 ffffffff81030168 > > ffff880075507ed8 ffffffff81d1104f 00000000000000c3 0000000000000000 > > Call Trace: > > [<ffffffff810aecb0>] clockevents_config_and_register+0x20/0x30 > > [<ffffffff81030168>] setup_APIC_timer+0xc8/0xd0 > > [<ffffffff81d1104f>] setup_boot_APIC_clock+0x4cc/0x4d8 > > [<ffffffff81d0f5de>] native_smp_prepare_cpus+0x3dd/0x3f0 > > [<ffffffff81d02ee9>] kernel_init_freeable+0xc3/0x205 > > [<ffffffff8177c910>] ? rest_init+0x90/0x90 > > [<ffffffff8177c91e>] kernel_init+0xe/0x120 > > [<ffffffff8178deec>] ret_from_fork+0x7c/0xb0 > > [<ffffffff8177c910>] ? rest_init+0x90/0x90 > > > > Prevent this from happening by: > > 1) Modifying try_msr_calibrate_tsc() to return calibration value or zero > > if it fails. > > 2) Check this return value in native_calibrate_tsc() and in case of zero > > fallback to use normal non-MSR based calibration. > > > > Reported-and-tested-by: Mika Westerberg <mika.westerb...@linux.intel.com> > > Signed-off-by: Thomas Gleixner <t...@linutronix.de> > > --- > > Thomas, I hope you don't mind that I added your SoB to the patch. It is > > after all from you. > > You just missed to add your own SOB which tells us that you conveyed > the patch.
Ah, right. Here it is, Signed-off-by: Mika Westerberg <mika.westerb...@linux.intel.com> Is that enough or do you want me to resend this patch? Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
