Re: UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29
> I think UBSAN has correctly identified a bug. I looked at the code in > v4.6. In file arch/x86/events/core.c, in the function > filter_events(), there is a loop starting at line 1554 that should go > over 10 event counters. But in file arch/x86/events/intel/p6.c, only > 8 event counters have been declared at line 9. > > I have a fix but do not for sure if its reasonable. I think we should > pass on the max_events for the pmu to filter_events() function and > change the loop condition accordingly. Can you apply the patch below > and test again? It compiles, but I have not tested it. Seems to work - warning is gone, everythins is detected as before. -- Meelis Roos (mr...@linux.ee)
Re: UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29
> I think UBSAN has correctly identified a bug. I looked at the code in > v4.6. In file arch/x86/events/core.c, in the function > filter_events(), there is a loop starting at line 1554 that should go > over 10 event counters. But in file arch/x86/events/intel/p6.c, only > 8 event counters have been declared at line 9. > > I have a fix but do not for sure if its reasonable. I think we should > pass on the max_events for the pmu to filter_events() function and > change the loop condition accordingly. Can you apply the patch below > and test again? It compiles, but I have not tested it. Seems to work - warning is gone, everythins is detected as before. -- Meelis Roos (mr...@linux.ee)
Re: UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29
On 16 May 2016 at 13:41, Meelis Roos <mr...@linux.ee> wrote: > Not sure if this is a genuine warning or a false positive but since some > UBSAN warnings have been real and google does not find report about this > specific warning, I'll send it in anyway. > > I have seen similar amd pmu warnings from UBSAN but I do not have any > amd machines from that time frame online for now, so p6 only. > > [0.15] Performance Events: p6 PMU driver. > [0.15] > ======== > [ 0.150000] UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29 > [0.15] index 8 is out of range for type 'u64 [8]' > [0.15] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0 #21 > [0.15] Hardware name: Dell Computer Corporation PowerEdge 1550/933 > , BIOS A09 12/10/2004 > [0.15] c13a4bcc 0046 f605de88 0008 c13d5188 > c17ddfd4 c13d5725 > [0.15] c176ae8c f605de8c c17ddfec 0202 0038 00752101 > 0002 > [0.15] 0297 00c2 c17d2b60 c102b14f > 0008 > [0.15] Call Trace: > [0.15] [] ? dump_stack+0x45/0x69 > [0.15] [] ? ubsan_epilogue+0x8/0x30 > [0.15] [] ? __ubsan_handle_out_of_bounds+0x55/0x60 > [0.15] [] ? __register_nmi_handler+0xbf/0x300 > [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 > [0.15] [] ? p6_pmu_event_map+0x3d/0x50 > [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 > [0.15] [] ? init_hw_perf_events+0x493/0x688 > [0.15] [] ? merge_attr+0x1d5/0x1d5 > [0.15] [] ? do_one_initcall+0x82/0x230 > [0.15] [] ? vprintk_default+0xf/0x20 > [0.15] [] ? printk+0x11/0x12 > [0.15] [] ? print_cpu_info+0x86/0x130 > [0.15] [] ? native_smp_prepare_cpus+0x40e/0x453 > [0.15] [] ? kernel_init_freeable+0x117/0x2fd > [0.15] [] ? kernel_init+0x6/0x100 > [0.15] [] ? ret_from_kernel_thread+0x21/0x38 > [0.15] [] ? rest_init+0x60/0x60 > [0.15] > > [0.15] > > [0.15] UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:9 > [0.15] load of address c16adf20 with insufficient space > [0.15] for an object of type 'const u64' > [0.15] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0 #21 > [0.15] Hardware name: Dell Computer Corporation PowerEdge 1550/933 > , BIOS A09 12/10/2004 > [0.15] c13a4bcc 0046 f605deb4 c16adf20 c13d5188 > c17ddfac c13d5229 > [0.15] c176a901 c17ddfc8 c176aca4 c176a95e c16adf20 0202 > 0008 > [0.15] c101841d 0008 c10183d0 0008 c1af0c78 c17d2c00 > f605df08 0001 > [0.15] Call Trace: > [0.15] [] ? dump_stack+0x45/0x69 > [0.15] [] ? ubsan_epilogue+0x8/0x30 > [0.15] [] ? __ubsan_handle_type_mismatch+0x79/0x150 > [0.15] [] ? p6_pmu_event_map+0x4d/0x50 > [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 > [0.15] [] ? init_hw_perf_events+0x493/0x688 > [0.15] [] ? merge_attr+0x1d5/0x1d5 > [0.15] [] ? do_one_initcall+0x82/0x230 > [0.15] [] ? vprintk_default+0xf/0x20 > [0.15] [] ? printk+0x11/0x12 > [0.15] [] ? print_cpu_info+0x86/0x130 > [0.15] [] ? native_smp_prepare_cpus+0x40e/0x453 > [0.15] [] ? kernel_init_freeable+0x117/0x2fd > [0.15] [] ? kernel_init+0x6/0x100 > [0.15] [] ? ret_from_kernel_thread+0x21/0x38 > [0.15] [] ? rest_init+0x60/0x60 > [0.15] > > [0.15] ... version:0 > [0.15] ... bit width: 32 > [0.15] ... generic registers: 2 > [0.15] ... value mask: > [0.15] ... max period: 7fff > [0.15] ... fixed-purpose events: 0 > [0.15] ... event mask: 0003 > I think UBSAN has correctly identified a bug. I looked at the code in v4.6. In file arch/x86/events/core.c, in the function filter_events(), there is a loop starting at line 1554 that should go over 10 event counters. But in file arch/x86/events/intel/p6.c, only 8 event counters have been declared at line 9. I have a fix but do not for sure if its reasonable. I think we should pass on the max_events for the pmu to filter_events() function and change
Re: UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29
On 16 May 2016 at 13:41, Meelis Roos wrote: > Not sure if this is a genuine warning or a false positive but since some > UBSAN warnings have been real and google does not find report about this > specific warning, I'll send it in anyway. > > I have seen similar amd pmu warnings from UBSAN but I do not have any > amd machines from that time frame online for now, so p6 only. > > [0.15] Performance Events: p6 PMU driver. > [0.15] > ==== > [0.150000] UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29 > [0.15] index 8 is out of range for type 'u64 [8]' > [0.15] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0 #21 > [0.15] Hardware name: Dell Computer Corporation PowerEdge 1550/933 > , BIOS A09 12/10/2004 > [0.15] c13a4bcc 0046 f605de88 0008 c13d5188 > c17ddfd4 c13d5725 > [0.15] c176ae8c f605de8c c17ddfec 0202 0038 00752101 > 0002 > [0.15] 0297 00c2 c17d2b60 c102b14f > 0008 > [0.15] Call Trace: > [0.15] [] ? dump_stack+0x45/0x69 > [0.15] [] ? ubsan_epilogue+0x8/0x30 > [0.15] [] ? __ubsan_handle_out_of_bounds+0x55/0x60 > [0.15] [] ? __register_nmi_handler+0xbf/0x300 > [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 > [0.15] [] ? p6_pmu_event_map+0x3d/0x50 > [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 > [0.15] [] ? init_hw_perf_events+0x493/0x688 > [0.15] [] ? merge_attr+0x1d5/0x1d5 > [0.15] [] ? do_one_initcall+0x82/0x230 > [0.15] [] ? vprintk_default+0xf/0x20 > [0.15] [] ? printk+0x11/0x12 > [0.15] [] ? print_cpu_info+0x86/0x130 > [0.15] [] ? native_smp_prepare_cpus+0x40e/0x453 > [0.15] [] ? kernel_init_freeable+0x117/0x2fd > [0.15] [] ? kernel_init+0x6/0x100 > [0.15] [] ? ret_from_kernel_thread+0x21/0x38 > [0.15] [] ? rest_init+0x60/0x60 > [0.15] > > [0.15] > > [0.15] UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:9 > [0.15] load of address c16adf20 with insufficient space > [0.15] for an object of type 'const u64' > [0.15] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0 #21 > [0.15] Hardware name: Dell Computer Corporation PowerEdge 1550/933 > , BIOS A09 12/10/2004 > [0.15] c13a4bcc 0046 f605deb4 c16adf20 c13d5188 > c17ddfac c13d5229 > [0.15] c176a901 c17ddfc8 c176aca4 c176a95e c16adf20 0202 > 0008 > [0.15] c101841d 0008 c10183d0 0008 c1af0c78 c17d2c00 > f605df08 0001 > [0.15] Call Trace: > [0.15] [] ? dump_stack+0x45/0x69 > [0.15] [] ? ubsan_epilogue+0x8/0x30 > [0.15] [] ? __ubsan_handle_type_mismatch+0x79/0x150 > [0.15] [] ? p6_pmu_event_map+0x4d/0x50 > [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 > [0.15] [] ? init_hw_perf_events+0x493/0x688 > [0.15] [] ? merge_attr+0x1d5/0x1d5 > [0.15] [] ? do_one_initcall+0x82/0x230 > [0.15] [] ? vprintk_default+0xf/0x20 > [0.15] [] ? printk+0x11/0x12 > [0.15] [] ? print_cpu_info+0x86/0x130 > [0.15] [] ? native_smp_prepare_cpus+0x40e/0x453 > [0.15] [] ? kernel_init_freeable+0x117/0x2fd > [0.15] [] ? kernel_init+0x6/0x100 > [0.15] [] ? ret_from_kernel_thread+0x21/0x38 > [0.15] [] ? rest_init+0x60/0x60 > [0.15] > > [0.15] ... version:0 > [0.15] ... bit width: 32 > [0.15] ... generic registers: 2 > [0.15] ... value mask: > [0.15] ... max period: 7fff > [0.15] ... fixed-purpose events: 0 > [0.15] ... event mask: 0003 > I think UBSAN has correctly identified a bug. I looked at the code in v4.6. In file arch/x86/events/core.c, in the function filter_events(), there is a loop starting at line 1554 that should go over 10 event counters. But in file arch/x86/events/intel/p6.c, only 8 event counters have been declared at line 9. I have a fix but do not for sure if its reasonable. I think we should pass on the max_events for the pmu to filter_events() function and change the loop condition a
UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29
Not sure if this is a genuine warning or a false positive but since some UBSAN warnings have been real and google does not find report about this specific warning, I'll send it in anyway. I have seen similar amd pmu warnings from UBSAN but I do not have any amd machines from that time frame online for now, so p6 only. [0.15] Performance Events: p6 PMU driver. [0.15] [0.15] UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29 [0.15] index 8 is out of range for type 'u64 [8]' [0.15] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0 #21 [0.15] Hardware name: Dell Computer Corporation PowerEdge 1550/933 , BIOS A09 12/10/2004 [0.15] c13a4bcc 0046 f605de88 0008 c13d5188 c17ddfd4 c13d5725 [0.15] c176ae8c f605de8c c17ddfec 0202 0038 00752101 0002 [0.15] 0297 00c2 c17d2b60 c102b14f 0008 [0.15] Call Trace: [0.15] [] ? dump_stack+0x45/0x69 [0.15] [] ? ubsan_epilogue+0x8/0x30 [0.15] [] ? __ubsan_handle_out_of_bounds+0x55/0x60 [0.15] [] ? __register_nmi_handler+0xbf/0x300 [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 [0.15] [] ? p6_pmu_event_map+0x3d/0x50 [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 [0.15] [] ? init_hw_perf_events+0x493/0x688 [0.15] [] ? merge_attr+0x1d5/0x1d5 [0.15] [] ? do_one_initcall+0x82/0x230 [0.15] [] ? vprintk_default+0xf/0x20 [0.15] [] ? printk+0x11/0x12 [0.15] [] ? print_cpu_info+0x86/0x130 [0.15] [] ? native_smp_prepare_cpus+0x40e/0x453 [0.15] [] ? kernel_init_freeable+0x117/0x2fd [0.15] [] ? kernel_init+0x6/0x100 [0.15] [] ? ret_from_kernel_thread+0x21/0x38 [0.15] [] ? rest_init+0x60/0x60 [0.15] [0.15] [0.15] UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:9 [0.15] load of address c16adf20 with insufficient space [0.15] for an object of type 'const u64' [0.15] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0 #21 [0.15] Hardware name: Dell Computer Corporation PowerEdge 1550/933 , BIOS A09 12/10/2004 [0.15] c13a4bcc 0046 f605deb4 c16adf20 c13d5188 c17ddfac c13d5229 [0.15] c176a901 c17ddfc8 c176aca4 c176a95e c16adf20 0202 0008 [0.15] c101841d 0008 c10183d0 0008 c1af0c78 c17d2c00 f605df08 0001 [0.15] Call Trace: [0.15] [] ? dump_stack+0x45/0x69 [0.15] [] ? ubsan_epilogue+0x8/0x30 [0.15] [] ? __ubsan_handle_type_mismatch+0x79/0x150 [0.15] [] ? p6_pmu_event_map+0x4d/0x50 [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 [0.15] [] ? init_hw_perf_events+0x493/0x688 [0.15] [] ? merge_attr+0x1d5/0x1d5 [0.15] [] ? do_one_initcall+0x82/0x230 [0.15] [] ? vprintk_default+0xf/0x20 [0.15] [] ? printk+0x11/0x12 [0.15] [] ? print_cpu_info+0x86/0x130 [0.15] [] ? native_smp_prepare_cpus+0x40e/0x453 [0.15] [] ? kernel_init_freeable+0x117/0x2fd [0.15] [] ? kernel_init+0x6/0x100 [0.15] [] ? ret_from_kernel_thread+0x21/0x38 [0.15] [] ? rest_init+0x60/0x60 [0.15] [0.15] ... version:0 [0.15] ... bit width: 32 [0.15] ... generic registers: 2 [0.15] ... value mask: [0.15] ... max period: 7fff [0.15] ... fixed-purpose events: 0 [0.15] ... event mask: 0003 -- Meelis Roos (mr...@linux.ee)
UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29
Not sure if this is a genuine warning or a false positive but since some UBSAN warnings have been real and google does not find report about this specific warning, I'll send it in anyway. I have seen similar amd pmu warnings from UBSAN but I do not have any amd machines from that time frame online for now, so p6 only. [0.15] Performance Events: p6 PMU driver. [0.15] [0.15] UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:29 [0.15] index 8 is out of range for type 'u64 [8]' [0.15] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0 #21 [0.15] Hardware name: Dell Computer Corporation PowerEdge 1550/933 , BIOS A09 12/10/2004 [0.15] c13a4bcc 0046 f605de88 0008 c13d5188 c17ddfd4 c13d5725 [0.15] c176ae8c f605de8c c17ddfec 0202 0038 00752101 0002 [0.15] 0297 00c2 c17d2b60 c102b14f 0008 [0.15] Call Trace: [0.15] [] ? dump_stack+0x45/0x69 [0.15] [] ? ubsan_epilogue+0x8/0x30 [0.15] [] ? __ubsan_handle_out_of_bounds+0x55/0x60 [0.15] [] ? __register_nmi_handler+0xbf/0x300 [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 [0.15] [] ? p6_pmu_event_map+0x3d/0x50 [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 [0.15] [] ? init_hw_perf_events+0x493/0x688 [0.15] [] ? merge_attr+0x1d5/0x1d5 [0.15] [] ? do_one_initcall+0x82/0x230 [0.15] [] ? vprintk_default+0xf/0x20 [0.15] [] ? printk+0x11/0x12 [0.15] [] ? print_cpu_info+0x86/0x130 [0.15] [] ? native_smp_prepare_cpus+0x40e/0x453 [0.15] [] ? kernel_init_freeable+0x117/0x2fd [0.15] [] ? kernel_init+0x6/0x100 [0.15] [] ? ret_from_kernel_thread+0x21/0x38 [0.15] [] ? rest_init+0x60/0x60 [0.15] [0.15] [0.15] UBSAN: Undefined behaviour in arch/x86/events/intel/p6.c:115:9 [0.15] load of address c16adf20 with insufficient space [0.15] for an object of type 'const u64' [0.15] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0 #21 [0.15] Hardware name: Dell Computer Corporation PowerEdge 1550/933 , BIOS A09 12/10/2004 [0.15] c13a4bcc 0046 f605deb4 c16adf20 c13d5188 c17ddfac c13d5229 [0.15] c176a901 c17ddfc8 c176aca4 c176a95e c16adf20 0202 0008 [0.15] c101841d 0008 c10183d0 0008 c1af0c78 c17d2c00 f605df08 0001 [0.15] Call Trace: [0.15] [] ? dump_stack+0x45/0x69 [0.15] [] ? ubsan_epilogue+0x8/0x30 [0.15] [] ? __ubsan_handle_type_mismatch+0x79/0x150 [0.15] [] ? p6_pmu_event_map+0x4d/0x50 [0.15] [] ? p4_pmu_schedule_events+0x740/0x740 [0.15] [] ? init_hw_perf_events+0x493/0x688 [0.15] [] ? merge_attr+0x1d5/0x1d5 [0.15] [] ? do_one_initcall+0x82/0x230 [0.15] [] ? vprintk_default+0xf/0x20 [0.15] [] ? printk+0x11/0x12 [0.15] [] ? print_cpu_info+0x86/0x130 [0.15] [] ? native_smp_prepare_cpus+0x40e/0x453 [0.15] [] ? kernel_init_freeable+0x117/0x2fd [0.15] [] ? kernel_init+0x6/0x100 [0.15] [] ? ret_from_kernel_thread+0x21/0x38 [0.15] [] ? rest_init+0x60/0x60 [0.15] [0.15] ... version:0 [0.15] ... bit width: 32 [0.15] ... generic registers: 2 [0.15] ... value mask: [0.15] ... max period: 7fff [0.15] ... fixed-purpose events: 0 [0.15] ... event mask: 0003 -- Meelis Roos (mr...@linux.ee)
