lkml.org 
[lkml]   [2018]   [Jan]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: "BUG: using smp_processor_id() in preemptible" with KPTI on 4.14.11
On Thu, 4 Jan 2018, Thomas Zeitlhofer wrote:
> On Thu, Jan 04, 2018 at 01:55:28PM +0100, Greg Kroah-Hartman wrote:
> > > > > > on an Ivybridge CPU, I get with 4.14.11:
> > > > > >
> > > > > > BUG: using smp_processor_id() in preemptible [00000000] code: ovsdb-server/4510
> > > > > > caller is native_flush_tlb_single+0x57/0xc0
> > > > > > CPU: 3 PID: 4510 Comm: ovsdb-server Not tainted 4.14.11-kvm-00434-gcd0b8eb84f5c #3
> > > > > > Hardware name: MSI MS-7798/B75MA-P45 (MS-7798), BIOS V1.9 09/30/2013
> > > > > > Call Trace:
> > > > > > dump_stack+0x5c/0x86
> > > > > > check_preemption_disabled+0xdd/0xe0
> > > > > > native_flush_tlb_single+0x57/0xc0
> > > > > > ? __set_pte_vaddr+0x2d/0x40
> > > > > > __set_pte_vaddr+0x2d/0x40
> > > > > > set_pte_vaddr+0x2f/0x40
> > > > > > cea_set_pte+0x30/0x40
> > > > > > ds_update_cea.constprop.4+0x4d/0x70
> > > > > > reserve_ds_buffers+0x159/0x410
> > > > > > ? wp_page_copy+0x36d/0x6a0
> > > > > > x86_reserve_hardware+0x150/0x160
> > > > > > x86_pmu_event_init+0x3e/0x1f0
> > > > > > perf_try_init_event+0x69/0x80
> > > > > > perf_event_alloc+0x652/0x740
> > > > > > SyS_perf_event_open+0x3f6/0xd60
> > > > > > do_syscall_64+0x5c/0x190
> > > > > > entry_SYSCALL64_slow_path+0x25/0x25
> > > > > > RIP: 0033:0x74a1d94580b9
> > > > > > RSP: 002b:00007fff0c01d5d8 EFLAGS: 00000206 ORIG_RAX: 000000000000012a
> > > > > > RAX: ffffffffffffffda RBX: 00007fff0c01d7b0 RCX: 000074a1d94580b9
> > > > > > RDX: 00000000ffffffff RSI: 0000000000000000 RDI: 00007fff0c01d5e0
> > > > > > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000007000000000
> > > > > > R10: 00000000ffffffff R11: 0000000000000206 R12: 0000000000000008
> > > > > > R13: 0000000000000000 R14: 00007fff0c01d790 R15: 00005df43a799600
> > > > > >
> > > > > > This does not show up when booting with pti=off.

Right, because the code path is not invoked ....

> > Odd, does 4.15-rc6 also trigger the same error?
>
> Yes:
>
> BUG: using smp_processor_id() in preemptible [00000000] code: ovsdb-server/4498
> caller is native_flush_tlb_single+0x57/0xc0
> CPU: 2 PID: 4498 Comm: ovsdb-server Not tainted 4.15.0-rc6-kvm-00423-gea1908c252eb #3
> Hardware name: MSI MS-7798/B75MA-P45 (MS-7798), BIOS V1.9 09/30/2013
> Call Trace:
> dump_stack+0x5c/0x86
> check_preemption_disabled+0xdd/0xe0
> native_flush_tlb_single+0x57/0xc0
> ? __set_pte_vaddr+0x2d/0x40
> __set_pte_vaddr+0x2d/0x40
> set_pte_vaddr+0x2f/0x40
> cea_set_pte+0x30/0x40
> ds_update_cea.constprop.4+0x4d/0x70
> reserve_ds_buffers+0x159/0x410
> ? wp_page_copy+0x370/0x6c0
> x86_reserve_hardware+0x150/0x160
> x86_pmu_event_init+0x3e/0x1f0
> perf_try_init_event+0x69/0x80
> perf_event_alloc+0x652/0x740
> SyS_perf_event_open+0x3f6/0xd60
> do_syscall_64+0x5c/0x190
> entry_SYSCALL64_slow_path+0x25/0x25
> RIP: 0033:0x72bff0a3c0b9
> RSP: 002b:00007ffed11c2f18 EFLAGS: 00000206 ORIG_RAX: 000000000000012a
> RAX: ffffffffffffffda RBX: 00007ffed11c30f0 RCX: 000072bff0a3c0b9
> RDX: 00000000ffffffff RSI: 0000000000000000 RDI: 00007ffed11c2f20
> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000007000000000
> R10: 00000000ffffffff R11: 0000000000000206 R12: 0000000000000008
> R13: 0000000000000000 R14: 00007ffed11c30d0 R15: 000060986ecfb600
> device ovs-system entered promiscuous mode
> netlink: 'ovs-vswitchd': attribute type 5 has an invalid length.
>
> In addition, with v4.15-rc6, netlink messages like in the last line show
> up, but I guess this is a different openvswitch related issue.
>
> > Thomas is working on an
> > issue with KALSR (see lkml with:
> > Subject: Re: "bad pmd" errors + oops with KPTI on 4.14.11 after loading X.509 certs
> > )
>
> Yes, I have also seen that thread, but I did not see any similarities to
> my issue. Anyway, I also tried out the patch proposed in
> https://lkml.org/lkml/2018/1/4/313 but it does not change anything here.

Correct. I'm looking into a fix. Stay tuned.

Thanks,

tglx

\
 
 \ /
  Last update: 2018-01-04 16:38    [W:0.102 / U:1.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site