next: i386-boot: clang-nightly: failed - intermittently - BUG: unable to handle page fault for address: 000024c0
Linux next-20230517 build with clang nightly for i386 boot fails intermittently. - i386: boot/clang-nightly-lkftconfig - failed
Please find detailed log here,
boot log: ===== [ 0.000000] Linux version 6.4.0-rc2-next-20230517 (tuxmake@tuxmake) (Debian clang version 17.0.0 (++20230507093322+728b8a139804-1~exp1~20230507093335.652), Debian LLD 17.0.0) #1 SMP PREEMPT_DYNAMIC @1684291209 <6>[ 0.000000] x86/fpu: x87 FPU will use FXSAVE <6>[ 0.000000] signal: max sigframe size: 1440 <6>[ 0.000000] BIOS-provided physical RAM map: <6>[ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable <6>[ 0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x000000007ffdefff] usable <6>[ 0.000000] BIOS-e820: [mem 0x000000007ffdf000-0x000000007fffffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x00000000b0000000-0x00000000bfffffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x00000000fed1c000-0x00000000fed1ffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x0000000100000000-0x000000017fffffff] usable <5>[ 0.000000] random: crng init done <5>[ 0.000000] Notice: NX (Execute Disable) protection cannot be enabled: non-PAE kernel! <7>[ 0.000000] e820: update [mem 0x00cfce20-0x00cfce2f] usable ==> usable <7>[ 0.000000] e820: update [mem 0x00cfce20-0x00cfce2f] usable ==> usable <6>[ 0.000000] extended physical RAM map: <6>[ 0.000000] reserve setup_data: [mem 0x0000000000000000-0x000000000009fbff] usable <6>[ 0.000000] reserve setup_data: [mem 0x000000000009fc00-0x000000000009ffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x00000000000f0000-0x00000000000fffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x0000000000100000-0x0000000000cfce1f] usable <6>[ 0.000000] reserve setup_data: [mem 0x0000000000cfce20-0x0000000000cfce2f] usable <6>[ 0.000000] reserve setup_data: [mem 0x0000000000cfce30-0x000000007ffdefff] usable <6>[ 0.000000] reserve setup_data: [mem 0x000000007ffdf000-0x000000007fffffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x00000000b0000000-0x00000000bfffffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x00000000fed1c000-0x00000000fed1ffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x0000000100000000-0x000000017fffffff] usable <6>[ 0.000000] SMBIOS 2.8 present. <6>[ 0.000000] DMI: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 <6>[ 0.000000] tsc: Fast TSC calibration using PIT <6>[ 0.000000] tsc: Detected 3000.002 MHz processor <7>[ 0.009140] e820: update [mem 0x00000000-0x00000fff] usable ==> reserved <7>[ 0.009369] e820: remove [mem 0x000a0000-0x000fffff] usable <6>[ 0.009688] last_pfn = 0x7ffdf max_arch_pfn = 0x100000 <6>[ 0.010313] x86/PAT: PAT not supported by the CPU. <6>[ 0.010476] x86/PAT: Configuration [0-7]: WB WT UC- UC WB WT UC- UC <6>[ 0.028035] found SMP MP-table at [mem 0x000f5ce0-0x000f5cef] <7>[ 0.029050] initial memory mapped: [mem 0x00000000-0x18ffffff] <6>[ 0.032814] ACPI: Early table checksum verification disabled <6>[ 0.033316] ACPI: RSDP 0x00000000000F5B10 000014 (v00 BOCHS ) <6>[ 0.033820] ACPI: RSDT 0x000000007FFE2319 000038 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.034477] ACPI: FACP 0x000000007FFE2109 0000F4 (v03 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035093] ACPI: DSDT 0x000000007FFE0040 0020C9 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035191] ACPI: FACS 0x000000007FFE0000 000040 <6>[ 0.035258] ACPI: APIC 0x000000007FFE21FD 000080 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035306] ACPI: HPET 0x000000007FFE227D 000038 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035336] ACPI: MCFG 0x000000007FFE22B5 00003C (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035365] ACPI: WAET 0x000000007FFE22F1 000028 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035470] ACPI: Reserving FACP table memory at [mem 0x7ffe2109-0x7ffe21fc] <6>[ 0.035522] ACPI: Reserving DSDT table memory at [mem 0x7ffe0040-0x7ffe2108] <6>[ 0.035533] ACPI: Reserving FACS table memory at [mem 0x7ffe0000-0x7ffe003f] <6>[ 0.035542] ACPI: Reserving APIC table memory at [mem 0x7ffe21fd-0x7ffe227c] <6>[ 0.035550] ACPI: Reserving HPET table memory at [mem 0x7ffe227d-0x7ffe22b4] <6>[ 0.035558] ACPI: Reserving MCFG table memory at [mem 0x7ffe22b5-0x7ffe22f0] <6>[ 0.035566] ACPI: Reserving WAET table memory at [mem 0x7ffe22f1-0x7ffe2318] <5>[ 0.036775] 1167MB HIGHMEM available. <5>[ 0.036823] 879MB LOWMEM available. <6>[ 0.036848] mapped low ram: 0 - 36ffe000 <6>[ 0.036864] low ram: 0 - 36ffe000 <6>[ 0.037465] Zone ranges: <6>[ 0.037490] DMA [mem 0x0000000000001000-0x0000000000ffffff] <6>[ 0.037576] Normal [mem 0x0000000001000000-0x0000000036ffdfff] <6>[ 0.037591] HighMem [mem 0x0000000036ffe000-0x000000007ffdefff] <6>[ 0.037610] Movable zone start for each node <6>[ 0.037625] Early memory node ranges <6>[ 0.037668] node 0: [mem 0x0000000000001000-0x000000000009efff] <6>[ 0.037741] node 0: [mem 0x0000000000100000-0x000000007ffdefff] <6>[ 0.037912] Initmem setup node 0 [mem 0x0000000000001000-0x000000007ffdefff] <6>[ 0.039699] On node 0, zone DMA: 1 pages in unavailable ranges <6>[ 0.040493] On node 0, zone DMA: 97 pages in unavailable ranges <6>[ 0.068623] Using APIC driver default <6>[ 0.069096] ACPI: PM-Timer IO Port: 0x608 <6>[ 0.069764] ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1]) <6>[ 0.070159] IOAPIC[0]: apic_id 0, version 32, address 0xfec00000, GSI 0-23 <6>[ 0.070278] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl) <6>[ 0.070576] ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 high level) <6>[ 0.070611] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level) <6>[ 0.070722] ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 high level) <6>[ 0.070735] ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 high level) <6>[ 0.070968] ACPI: Using ACPI (MADT) for SMP configuration information <6>[ 0.071240] smpboot: Allowing 2 CPUs, 0 hotplug CPUs <6>[ 0.072248] PM: hibernation: Registered nosave memory: [mem 0x00000000-0x00000fff] <6>[ 0.072334] PM: hibernation: Registered nosave memory: [mem 0x0009f000-0x0009ffff] <6>[ 0.072384] PM: hibernation: Registered nosave memory: [mem 0x000a0000-0x000effff] <6>[ 0.072394] PM: hibernation: Registered nosave memory: [mem 0x000f0000-0x000fffff] <6>[ 0.072405] PM: hibernation: Registered nosave memory: [mem 0x00cfc000-0x00cfcfff] <6>[ 0.072417] PM: hibernation: Registered nosave memory: [mem 0x00cfc000-0x00cfcfff] <6>[ 0.072636] [mem 0xc0000000-0xfed1bfff] available for PCI devices <6>[ 0.072683] Booting paravirtualized kernel on bare hardware <6>[ 0.073201] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1910969940391419 ns <6>[ 0.073674] setup_percpu: NR_CPUS:8 nr_cpumask_bits:2 nr_cpu_ids:2 nr_node_ids:1 <6>[ 0.075154] percpu: Embedded 31 pages/cpu s96372 r0 d30604 u126976 <7>[ 0.075652] pcpu-alloc: s96372 r0 d30604 u126976 alloc=31*4096 <7>[ 0.075742] pcpu-alloc: [0] 0 [0] 1 <5>[ 0.077147] Kernel command line: console=ttyS0,115200 rootwait root=/dev/sda debug verbose console_msg_format=syslog earlycon <5>[ 0.078730] Unknown kernel command line parameters "verbose", will be passed to user space. <6>[ 0.080340] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes, linear) <6>[ 0.081003] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes, linear) <6>[ 0.082840] Built 1 zonelists, mobility grouping on. Total pages: 521957 <6>[ 0.088082] mem auto-init: stack:all(zero), heap alloc:off, heap free:off <6>[ 0.088308] Initializing HighMem for node 0 (00036ffe:0007ffdf) <6>[ 0.454727] Initializing Movable for node 0 (00000000:00000000) <6>[ 0.459790] Checking if this processor honours the WP bit even in supervisor mode...Ok. <6>[ 0.460945] Memory: 2046372K/2096628K available (15688K kernel code, 2173K rwdata, 5772K rodata, 996K init, 780K bss, 50256K reserved, 0K cma-reserved, 1195908K highmem) <6>[ 0.466051] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=2, Nodes=1 <6>[ 0.468048] ftrace: allocating 54241 entries in 106 pages <6>[ 0.511020] ftrace: allocated 106 pages with 4 groups <6>[ 0.514727] trace event string verifier disabled <6>[ 0.519501] Dynamic Preempt: voluntary <6>[ 0.522734] rcu: Preemptible hierarchical RCU implementation. <6>[ 0.522756] rcu: RCU event tracing is enabled. <6>[ 0.522785] rcu: RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=2. <6>[ 0.522916] Trampoline variant of Tasks RCU enabled. <6>[ 0.522927] Rude variant of Tasks RCU enabled. <6>[ 0.523017] rcu: RCU calculated value of scheduler-enlistment delay is 100 jiffies. <6>[ 0.523045] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=2 <6>[ 0.538503] NR_IRQS: 2304, nr_irqs: 440, preallocated irqs: 16 <6>[ 0.543029] rcu: srcu_init: Setting srcu_struct sizes based on contention. <6>[ 0.546346] kfence: initialized - using 2097152 bytes for 255 objects at 0x(ptrval)-0x(ptrval) <6>[ 0.551378] Console: colour VGA+ 80x25 <6>[ 0.553103] printk: console [ttyS0] enabled <6>[ 0.626471] ACPI: Core revision 20230331 <6>[ 0.637882] APIC: Switch to symmetric I/O mode setup <6>[ 0.638348] Enabling APIC mode: Flat. Using 1 I/O APICs <6>[ 0.644118] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 <6>[ 0.650790] clocksource: tsc-early: mask: 0xffffffffffffffff max_cycles: 0x2b3e46fa93c, max_idle_ns: 440795237232 ns <6>[ 0.652683] Calibrating delay loop (skipped), value calculated using timer frequency.. 6000.00 BogoMIPS (lpj=3000002) <6>[ 0.654599] pid_max: default: 32768 minimum: 301 <6>[ 0.656733] LSM: initializing lsm=capability,selinux,integrity <6>[ 0.657713] SELinux: Initializing. <6>[ 0.660732] Mount-cache hash table entries: 2048 (order: 1, 8192 bytes, linear) <6>[ 0.661233] Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes, linear) <6>[ 0.682197] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0 <6>[ 0.682458] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0 <6>[ 0.682670] Spectre V1 : Mitigation: usercopy/swapgs barriers and __user pointer sanitization <6>[ 0.684632] Spectre V2 : Mitigation: Retpolines <6>[ 0.684930] Spectre V2 : Spectre v2 / SpectreRSB mitigation: Filling RSB on context switch <6>[ 0.685539] Spectre V2 : Spectre v2 / SpectreRSB : Filling RSB on VMEXIT <4>[ 0.686934] L1TF: Kernel not compiled for PAE. No mitigation for L1TF <6>[ 0.688097] MDS: Vulnerable: Clear CPU buffers attempted, no microcode <6>[ 0.688548] MMIO Stale Data: Unknown: No mitigations <0>[ 0.692458] __common_interrupt: 0.79 No irq handler for vector <0>[ 0.692458] __common_interrupt: 0.160 No irq handler for vector <1>[ 0.692458] BUG: unable to handle page fault for address: 000024c0 <1>[ 0.692458] #PF: user read access in kernel mode <1>[ 0.692458] #PF: error_code(0x0004) - not-present page <6>[ 0.692458] *pde = 00000000 <4>[ 0.692458] Oops: 0004 [#1] PREEMPT SMP <4>[ 0.692458] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-rc2-next-20230517 #1 <4>[ 0.692458] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 <4>[ 0.692458] EIP: 0x60 <4>[ 0.692458] Code: Unable to access opcode bytes at 0x36. <4>[ 0.692458] EAX: 00000060 EBX: 00000000 ECX: b51e0945 EDX: 006afcf0 <4>[ 0.692458] ESI: 00000060 EDI: 00000020 EBP: d86f7c04 ESP: d86f7ce0 <4>[ 0.692458] DS: 0000 ES: 0000 FS: 0000 GS: 0000 SS: 7c8c EFLAGS: 00324b92 <4>[ 0.692458] CR0: 80050033 CR2: 000024c0 CR3: 18a49000 CR4: 000006d0 <4>[ 0.692458] Call Trace: <4>[ 0.692458] ? vscnprintf+0x12/0x30 <4>[ 0.692458] ? prb_read_valid+0x31/0x50 <4>[ 0.692458] ? console_unlock+0x94/0xc0 <4>[ 0.692458] ? vprintk_emit+0xf4/0x230 <4>[ 0.692458] ? vprintk_emit+0xf4/0x230 <4>[ 0.692458] ? vprintk_default+0x15/0x20 <4>[ 0.692458] ? __is_insn_slot_addr+0x41/0x50 <4>[ 0.692458] ? kernel_text_address+0x7c/0x90 <4>[ 0.692458] ? __kernel_text_address+0x10/0x40 <4>[ 0.692458] ? show_trace_log_lvl.17+0x1f5/0x2f0 <4>[ 0.692458] ? __die_body+0x54/0x90 <4>[ 0.692458] ? __die+0x70/0x80 <4>[ 0.692458] ? page_fault_oops+0x2d3/0x310 <4>[ 0.692458] ? kernelmode_fixup_or_oops+0xa5/0xc0 <4>[ 0.692458] ? __bad_area_nosemaphore+0x59/0x1d0 <4>[ 0.692458] ? bad_area_nosemaphore+0x12/0x20 <4>[ 0.692458] ? do_user_addr_fault+0x156/0x400 <4>[ 0.692458] ? irqentry_enter+0x32/0x38 <4>[ 0.692458] ? trace_hardirqs_off_finish+0x2c/0x70 <4>[ 0.692458] ? exc_page_fault+0x50/0x154 <4>[ 0.692458] ? pvclock_clocksource_read_nowd+0xdc/0xdc <4>[ 0.692458] ? handle_exception+0x133/0x133 <4>[ 0.692458] ? pvclock_clocksource_read_nowd+0xdc/0xdc <4>[ 0.692458] Modules linked in: <4>[ 0.692458] CR2: 00000000000024c0 <4>[ 0.692458] ---[ end trace 0000000000000000 ]--- <4>[ 0.692458] EIP: 0x60 <4>[ 0.692458] Code: Unable to access opcode bytes at 0x36. <4>[ 0.692458] EAX: 00000060 EBX: 00000000 ECX: b51e0945 EDX: 006afcf0 <4>[ 0.692458] ESI: 00000060 EDI: 00000020 EBP: d86f7c04 ESP: d86f7ce0 <4>[ 0.692458] DS: 0000 ES: 0000 FS: 0000 GS: 0000 SS: 7c8c EFLAGS: 00324b92 <4>[ 0.692458] CR0: 80050033 CR2: 000024c0 CR3: 18a49000 CR4: 000006d0 <0>[ 0.692458] Kernel panic - not syncing: Attempted to kill the idle task! <0>[ 0.692458] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- poweroff
logs: === - https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20230517/tes... - https://tuxapi.tuxsuite.com/v1/groups/linaro/projects/lkft/tests/2PtyoY5qEJr...
Steps to reproduce intermittently, ============= # To install tuxrun on your system globally: # sudo pip3 install -U tuxrun==0.42.0 # # See https://tuxrun.org/ for complete documentation.
tuxrun \ --runtime podman \ --device qemu-i386 \ --kernel https://storage.tuxsuite.com/public/linaro/lkft/builds/2PtylXBvODt99O8r9YKOE... \ --modules https://storage.tuxsuite.com/public/linaro/lkft/builds/2PtylXBvODt99O8r9YKOE... \ --rootfs https://storage.tuxsuite.com/public/linaro/lkft/oebuilds/2PeQhkn36JqPowQBZge... \ --parameters SKIPFILE=skipfile-lkft.yaml \ --parameters SHARD_NUMBER=10 \ --parameters SHARD_INDEX=2 \ --image docker.io/lavasoftware/lava-dispatcher:2023.01.0020.gc1598238f \ --tests ltp-syscalls \ --timeouts boot=15 ltp-syscalls=50
-- Linaro LKFT https://lkft.linaro.org
On Wed, May 17, 2023 at 8:21 AM Naresh Kamboju naresh.kamboju@linaro.org wrote:
Linux next-20230517 build with clang nightly for i386 boot fails intermittently.
Keyword: intermittently. That will make tracking this down fun.
Our CI also hit a boot failure on tip/master with the same splat: https://github.com/ClangBuiltLinux/continuous-integration2/actions/runs/4998... Though the CI pulled down a SHA 0932447780e1f9a43bf68ef7fe3d9b41b46d58fc which looks weird on https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=09324...
Notice: this object is not reachable from any branch.
That this failed in -next and -tip in the same way makes me wonder if something affecting this is coming in via -tip? Maybe the splat looks familiar to x86 folks?
I haven't been able to reproduce locally when my machine is relatively load-less. If I do a kernel build in the background, I was able to get QEMU to hang, but without any splat. That was using tip/master @ f81d8f759e7f.
Naresh, when you say "intermittent" do you have any data on the relative frequency of this boot failure? (Also, please make sure to use llvm@lists.linux.dev in the future; we moved mailing lists years ago).
Looks like our CI report linked above has an additional splat though via apply_alternatives and optimize_nops.
[ 0.166742] Code: Unable to access opcode bytes at 0x36.
Peter, that smells like perhaps either: commit b6c881b248ef ("x86/alternative: Complicate optimize_nops() some more") commit 6c480f222128 ("x86/alternative: Rewrite optimize_nops() some")
Looks like BP committed them May 11; maybe just recently they were merged into tip/master?
- i386: boot/clang-nightly-lkftconfig - failed
Please find detailed log here,
boot log:
[ 0.000000] Linux version 6.4.0-rc2-next-20230517 (tuxmake@tuxmake) (Debian clang version 17.0.0 (++20230507093322+728b8a139804-1~exp1~20230507093335.652), Debian LLD 17.0.0) #1 SMP PREEMPT_DYNAMIC @1684291209 <6>[ 0.000000] x86/fpu: x87 FPU will use FXSAVE <6>[ 0.000000] signal: max sigframe size: 1440 <6>[ 0.000000] BIOS-provided physical RAM map: <6>[ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable <6>[ 0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x000000007ffdefff] usable <6>[ 0.000000] BIOS-e820: [mem 0x000000007ffdf000-0x000000007fffffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x00000000b0000000-0x00000000bfffffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x00000000fed1c000-0x00000000fed1ffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved <6>[ 0.000000] BIOS-e820: [mem 0x0000000100000000-0x000000017fffffff] usable <5>[ 0.000000] random: crng init done <5>[ 0.000000] Notice: NX (Execute Disable) protection cannot be enabled: non-PAE kernel! <7>[ 0.000000] e820: update [mem 0x00cfce20-0x00cfce2f] usable ==> usable <7>[ 0.000000] e820: update [mem 0x00cfce20-0x00cfce2f] usable ==> usable <6>[ 0.000000] extended physical RAM map: <6>[ 0.000000] reserve setup_data: [mem 0x0000000000000000-0x000000000009fbff] usable <6>[ 0.000000] reserve setup_data: [mem 0x000000000009fc00-0x000000000009ffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x00000000000f0000-0x00000000000fffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x0000000000100000-0x0000000000cfce1f] usable <6>[ 0.000000] reserve setup_data: [mem 0x0000000000cfce20-0x0000000000cfce2f] usable <6>[ 0.000000] reserve setup_data: [mem 0x0000000000cfce30-0x000000007ffdefff] usable <6>[ 0.000000] reserve setup_data: [mem 0x000000007ffdf000-0x000000007fffffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x00000000b0000000-0x00000000bfffffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x00000000fed1c000-0x00000000fed1ffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved <6>[ 0.000000] reserve setup_data: [mem 0x0000000100000000-0x000000017fffffff] usable <6>[ 0.000000] SMBIOS 2.8 present. <6>[ 0.000000] DMI: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 <6>[ 0.000000] tsc: Fast TSC calibration using PIT <6>[ 0.000000] tsc: Detected 3000.002 MHz processor <7>[ 0.009140] e820: update [mem 0x00000000-0x00000fff] usable ==> reserved <7>[ 0.009369] e820: remove [mem 0x000a0000-0x000fffff] usable <6>[ 0.009688] last_pfn = 0x7ffdf max_arch_pfn = 0x100000 <6>[ 0.010313] x86/PAT: PAT not supported by the CPU. <6>[ 0.010476] x86/PAT: Configuration [0-7]: WB WT UC- UC WB WT UC- UC <6>[ 0.028035] found SMP MP-table at [mem 0x000f5ce0-0x000f5cef] <7>[ 0.029050] initial memory mapped: [mem 0x00000000-0x18ffffff] <6>[ 0.032814] ACPI: Early table checksum verification disabled <6>[ 0.033316] ACPI: RSDP 0x00000000000F5B10 000014 (v00 BOCHS ) <6>[ 0.033820] ACPI: RSDT 0x000000007FFE2319 000038 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.034477] ACPI: FACP 0x000000007FFE2109 0000F4 (v03 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035093] ACPI: DSDT 0x000000007FFE0040 0020C9 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035191] ACPI: FACS 0x000000007FFE0000 000040 <6>[ 0.035258] ACPI: APIC 0x000000007FFE21FD 000080 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035306] ACPI: HPET 0x000000007FFE227D 000038 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035336] ACPI: MCFG 0x000000007FFE22B5 00003C (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035365] ACPI: WAET 0x000000007FFE22F1 000028 (v01 BOCHS BXPC 00000001 BXPC 00000001) <6>[ 0.035470] ACPI: Reserving FACP table memory at [mem 0x7ffe2109-0x7ffe21fc] <6>[ 0.035522] ACPI: Reserving DSDT table memory at [mem 0x7ffe0040-0x7ffe2108] <6>[ 0.035533] ACPI: Reserving FACS table memory at [mem 0x7ffe0000-0x7ffe003f] <6>[ 0.035542] ACPI: Reserving APIC table memory at [mem 0x7ffe21fd-0x7ffe227c] <6>[ 0.035550] ACPI: Reserving HPET table memory at [mem 0x7ffe227d-0x7ffe22b4] <6>[ 0.035558] ACPI: Reserving MCFG table memory at [mem 0x7ffe22b5-0x7ffe22f0] <6>[ 0.035566] ACPI: Reserving WAET table memory at [mem 0x7ffe22f1-0x7ffe2318] <5>[ 0.036775] 1167MB HIGHMEM available. <5>[ 0.036823] 879MB LOWMEM available. <6>[ 0.036848] mapped low ram: 0 - 36ffe000 <6>[ 0.036864] low ram: 0 - 36ffe000 <6>[ 0.037465] Zone ranges: <6>[ 0.037490] DMA [mem 0x0000000000001000-0x0000000000ffffff] <6>[ 0.037576] Normal [mem 0x0000000001000000-0x0000000036ffdfff] <6>[ 0.037591] HighMem [mem 0x0000000036ffe000-0x000000007ffdefff] <6>[ 0.037610] Movable zone start for each node <6>[ 0.037625] Early memory node ranges <6>[ 0.037668] node 0: [mem 0x0000000000001000-0x000000000009efff] <6>[ 0.037741] node 0: [mem 0x0000000000100000-0x000000007ffdefff] <6>[ 0.037912] Initmem setup node 0 [mem 0x0000000000001000-0x000000007ffdefff] <6>[ 0.039699] On node 0, zone DMA: 1 pages in unavailable ranges <6>[ 0.040493] On node 0, zone DMA: 97 pages in unavailable ranges <6>[ 0.068623] Using APIC driver default <6>[ 0.069096] ACPI: PM-Timer IO Port: 0x608 <6>[ 0.069764] ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1]) <6>[ 0.070159] IOAPIC[0]: apic_id 0, version 32, address 0xfec00000, GSI 0-23 <6>[ 0.070278] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl) <6>[ 0.070576] ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 high level) <6>[ 0.070611] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level) <6>[ 0.070722] ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 high level) <6>[ 0.070735] ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 high level) <6>[ 0.070968] ACPI: Using ACPI (MADT) for SMP configuration information <6>[ 0.071240] smpboot: Allowing 2 CPUs, 0 hotplug CPUs <6>[ 0.072248] PM: hibernation: Registered nosave memory: [mem 0x00000000-0x00000fff] <6>[ 0.072334] PM: hibernation: Registered nosave memory: [mem 0x0009f000-0x0009ffff] <6>[ 0.072384] PM: hibernation: Registered nosave memory: [mem 0x000a0000-0x000effff] <6>[ 0.072394] PM: hibernation: Registered nosave memory: [mem 0x000f0000-0x000fffff] <6>[ 0.072405] PM: hibernation: Registered nosave memory: [mem 0x00cfc000-0x00cfcfff] <6>[ 0.072417] PM: hibernation: Registered nosave memory: [mem 0x00cfc000-0x00cfcfff] <6>[ 0.072636] [mem 0xc0000000-0xfed1bfff] available for PCI devices <6>[ 0.072683] Booting paravirtualized kernel on bare hardware <6>[ 0.073201] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1910969940391419 ns <6>[ 0.073674] setup_percpu: NR_CPUS:8 nr_cpumask_bits:2 nr_cpu_ids:2 nr_node_ids:1 <6>[ 0.075154] percpu: Embedded 31 pages/cpu s96372 r0 d30604 u126976 <7>[ 0.075652] pcpu-alloc: s96372 r0 d30604 u126976 alloc=31*4096 <7>[ 0.075742] pcpu-alloc: [0] 0 [0] 1 <5>[ 0.077147] Kernel command line: console=ttyS0,115200 rootwait root=/dev/sda debug verbose console_msg_format=syslog earlycon <5>[ 0.078730] Unknown kernel command line parameters "verbose", will be passed to user space. <6>[ 0.080340] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes, linear) <6>[ 0.081003] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes, linear) <6>[ 0.082840] Built 1 zonelists, mobility grouping on. Total pages: 521957 <6>[ 0.088082] mem auto-init: stack:all(zero), heap alloc:off, heap free:off <6>[ 0.088308] Initializing HighMem for node 0 (00036ffe:0007ffdf) <6>[ 0.454727] Initializing Movable for node 0 (00000000:00000000) <6>[ 0.459790] Checking if this processor honours the WP bit even in supervisor mode...Ok. <6>[ 0.460945] Memory: 2046372K/2096628K available (15688K kernel code, 2173K rwdata, 5772K rodata, 996K init, 780K bss, 50256K reserved, 0K cma-reserved, 1195908K highmem) <6>[ 0.466051] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=2, Nodes=1 <6>[ 0.468048] ftrace: allocating 54241 entries in 106 pages <6>[ 0.511020] ftrace: allocated 106 pages with 4 groups <6>[ 0.514727] trace event string verifier disabled <6>[ 0.519501] Dynamic Preempt: voluntary <6>[ 0.522734] rcu: Preemptible hierarchical RCU implementation. <6>[ 0.522756] rcu: RCU event tracing is enabled. <6>[ 0.522785] rcu: RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=2. <6>[ 0.522916] Trampoline variant of Tasks RCU enabled. <6>[ 0.522927] Rude variant of Tasks RCU enabled. <6>[ 0.523017] rcu: RCU calculated value of scheduler-enlistment delay is 100 jiffies. <6>[ 0.523045] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=2 <6>[ 0.538503] NR_IRQS: 2304, nr_irqs: 440, preallocated irqs: 16 <6>[ 0.543029] rcu: srcu_init: Setting srcu_struct sizes based on contention. <6>[ 0.546346] kfence: initialized - using 2097152 bytes for 255 objects at 0x(ptrval)-0x(ptrval) <6>[ 0.551378] Console: colour VGA+ 80x25 <6>[ 0.553103] printk: console [ttyS0] enabled <6>[ 0.626471] ACPI: Core revision 20230331 <6>[ 0.637882] APIC: Switch to symmetric I/O mode setup <6>[ 0.638348] Enabling APIC mode: Flat. Using 1 I/O APICs <6>[ 0.644118] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1 <6>[ 0.650790] clocksource: tsc-early: mask: 0xffffffffffffffff max_cycles: 0x2b3e46fa93c, max_idle_ns: 440795237232 ns <6>[ 0.652683] Calibrating delay loop (skipped), value calculated using timer frequency.. 6000.00 BogoMIPS (lpj=3000002) <6>[ 0.654599] pid_max: default: 32768 minimum: 301 <6>[ 0.656733] LSM: initializing lsm=capability,selinux,integrity <6>[ 0.657713] SELinux: Initializing. <6>[ 0.660732] Mount-cache hash table entries: 2048 (order: 1, 8192 bytes, linear) <6>[ 0.661233] Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes, linear) <6>[ 0.682197] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0 <6>[ 0.682458] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0 <6>[ 0.682670] Spectre V1 : Mitigation: usercopy/swapgs barriers and __user pointer sanitization <6>[ 0.684632] Spectre V2 : Mitigation: Retpolines <6>[ 0.684930] Spectre V2 : Spectre v2 / SpectreRSB mitigation: Filling RSB on context switch <6>[ 0.685539] Spectre V2 : Spectre v2 / SpectreRSB : Filling RSB on VMEXIT <4>[ 0.686934] L1TF: Kernel not compiled for PAE. No mitigation for L1TF <6>[ 0.688097] MDS: Vulnerable: Clear CPU buffers attempted, no microcode <6>[ 0.688548] MMIO Stale Data: Unknown: No mitigations <0>[ 0.692458] __common_interrupt: 0.79 No irq handler for vector <0>[ 0.692458] __common_interrupt: 0.160 No irq handler for vector <1>[ 0.692458] BUG: unable to handle page fault for address: 000024c0 <1>[ 0.692458] #PF: user read access in kernel mode <1>[ 0.692458] #PF: error_code(0x0004) - not-present page <6>[ 0.692458] *pde = 00000000 <4>[ 0.692458] Oops: 0004 [#1] PREEMPT SMP <4>[ 0.692458] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-rc2-next-20230517 #1 <4>[ 0.692458] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 <4>[ 0.692458] EIP: 0x60 <4>[ 0.692458] Code: Unable to access opcode bytes at 0x36. <4>[ 0.692458] EAX: 00000060 EBX: 00000000 ECX: b51e0945 EDX: 006afcf0 <4>[ 0.692458] ESI: 00000060 EDI: 00000020 EBP: d86f7c04 ESP: d86f7ce0 <4>[ 0.692458] DS: 0000 ES: 0000 FS: 0000 GS: 0000 SS: 7c8c EFLAGS: 00324b92 <4>[ 0.692458] CR0: 80050033 CR2: 000024c0 CR3: 18a49000 CR4: 000006d0 <4>[ 0.692458] Call Trace: <4>[ 0.692458] ? vscnprintf+0x12/0x30 <4>[ 0.692458] ? prb_read_valid+0x31/0x50 <4>[ 0.692458] ? console_unlock+0x94/0xc0 <4>[ 0.692458] ? vprintk_emit+0xf4/0x230 <4>[ 0.692458] ? vprintk_emit+0xf4/0x230 <4>[ 0.692458] ? vprintk_default+0x15/0x20 <4>[ 0.692458] ? __is_insn_slot_addr+0x41/0x50 <4>[ 0.692458] ? kernel_text_address+0x7c/0x90 <4>[ 0.692458] ? __kernel_text_address+0x10/0x40 <4>[ 0.692458] ? show_trace_log_lvl.17+0x1f5/0x2f0 <4>[ 0.692458] ? __die_body+0x54/0x90 <4>[ 0.692458] ? __die+0x70/0x80 <4>[ 0.692458] ? page_fault_oops+0x2d3/0x310 <4>[ 0.692458] ? kernelmode_fixup_or_oops+0xa5/0xc0 <4>[ 0.692458] ? __bad_area_nosemaphore+0x59/0x1d0 <4>[ 0.692458] ? bad_area_nosemaphore+0x12/0x20 <4>[ 0.692458] ? do_user_addr_fault+0x156/0x400 <4>[ 0.692458] ? irqentry_enter+0x32/0x38 <4>[ 0.692458] ? trace_hardirqs_off_finish+0x2c/0x70 <4>[ 0.692458] ? exc_page_fault+0x50/0x154 <4>[ 0.692458] ? pvclock_clocksource_read_nowd+0xdc/0xdc <4>[ 0.692458] ? handle_exception+0x133/0x133 <4>[ 0.692458] ? pvclock_clocksource_read_nowd+0xdc/0xdc <4>[ 0.692458] Modules linked in: <4>[ 0.692458] CR2: 00000000000024c0 <4>[ 0.692458] ---[ end trace 0000000000000000 ]--- <4>[ 0.692458] EIP: 0x60 <4>[ 0.692458] Code: Unable to access opcode bytes at 0x36. <4>[ 0.692458] EAX: 00000060 EBX: 00000000 ECX: b51e0945 EDX: 006afcf0 <4>[ 0.692458] ESI: 00000060 EDI: 00000020 EBP: d86f7c04 ESP: d86f7ce0 <4>[ 0.692458] DS: 0000 ES: 0000 FS: 0000 GS: 0000 SS: 7c8c EFLAGS: 00324b92 <4>[ 0.692458] CR0: 80050033 CR2: 000024c0 CR3: 18a49000 CR4: 000006d0 <0>[ 0.692458] Kernel panic - not syncing: Attempted to kill the idle task! <0>[ 0.692458] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- poweroff
logs:
- https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20230517/tes...
- https://tuxapi.tuxsuite.com/v1/groups/linaro/projects/lkft/tests/2PtyoY5qEJr...
Steps to reproduce intermittently,
# To install tuxrun on your system globally: # sudo pip3 install -U tuxrun==0.42.0 # # See https://tuxrun.org/ for complete documentation.
tuxrun \ --runtime podman \ --device qemu-i386 \ --kernel https://storage.tuxsuite.com/public/linaro/lkft/builds/2PtylXBvODt99O8r9YKOE... \ --modules https://storage.tuxsuite.com/public/linaro/lkft/builds/2PtylXBvODt99O8r9YKOE... \ --rootfs https://storage.tuxsuite.com/public/linaro/lkft/oebuilds/2PeQhkn36JqPowQBZge... \ --parameters SKIPFILE=skipfile-lkft.yaml \ --parameters SHARD_NUMBER=10 \ --parameters SHARD_INDEX=2 \ --image docker.io/lavasoftware/lava-dispatcher:2023.01.0020.gc1598238f \ --tests ltp-syscalls \ --timeouts boot=15 ltp-syscalls=50
-- Linaro LKFT https://lkft.linaro.org
On Wed, 17 May 2023 at 23:42, Nick Desaulniers ndesaulniers@google.com wrote:
On Wed, May 17, 2023 at 8:21 AM Naresh Kamboju naresh.kamboju@linaro.org wrote:
Linux next-20230517 build with clang nightly for i386 boot fails intermittently.
Keyword: intermittently. That will make tracking this down fun.
Our CI also hit a boot failure on tip/master with the same splat: https://github.com/ClangBuiltLinux/continuous-integration2/actions/runs/4998... Though the CI pulled down a SHA 0932447780e1f9a43bf68ef7fe3d9b41b46d58fc which looks weird on https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=09324...
Notice: this object is not reachable from any branch.
That this failed in -next and -tip in the same way makes me wonder if something affecting this is coming in via -tip? Maybe the splat looks familiar to x86 folks?
I haven't been able to reproduce locally when my machine is relatively load-less. If I do a kernel build in the background, I was able to get QEMU to hang, but without any splat. That was using tip/master @ f81d8f759e7f.
Naresh, when you say "intermittent" do you have any data on the relative frequency of this boot failure? (Also, please make sure to use llvm@lists.linux.dev in the future; we moved mailing lists years ago).
Noted: It is reproducible only 3 times out of 100 runs.
Looks like our CI report linked above has an additional splat though via apply_alternatives and optimize_nops.
[ 0.166742] Code: Unable to access opcode bytes at 0x36.
Peter, that smells like perhaps either: commit b6c881b248ef ("x86/alternative: Complicate optimize_nops() some more") commit 6c480f222128 ("x86/alternative: Rewrite optimize_nops() some")
Looks like BP committed them May 11; maybe just recently they were merged into tip/master?
- i386: boot/clang-nightly-lkftconfig - failed
- Naresh
On Wed, May 17, 2023 at 11:11:51AM -0700, Nick Desaulniers wrote:
On Wed, May 17, 2023 at 8:21 AM Naresh Kamboju naresh.kamboju@linaro.org wrote:
Linux next-20230517 build with clang nightly for i386 boot fails intermittently.
Keyword: intermittently. That will make tracking this down fun.
Our CI also hit a boot failure on tip/master with the same splat: https://github.com/ClangBuiltLinux/continuous-integration2/actions/runs/4998... Though the CI pulled down a SHA 0932447780e1f9a43bf68ef7fe3d9b41b46d58fc which looks weird on https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=09324...
Notice: this object is not reachable from any branch.
Github isn't willing to show me content unless I log in or somesuch nonsense.
That this failed in -next and -tip in the same way makes me wonder if something affecting this is coming in via -tip? Maybe the splat looks familiar to x86 folks?
I haven't been able to reproduce locally when my machine is relatively load-less. If I do a kernel build in the background, I was able to get QEMU to hang, but without any splat. That was using tip/master @ f81d8f759e7f.
Naresh, when you say "intermittent" do you have any data on the relative frequency of this boot failure? (Also, please make sure to use llvm@lists.linux.dev in the future; we moved mailing lists years ago).
Looks like our CI report linked above has an additional splat though via apply_alternatives and optimize_nops.
[ 0.166742] Code: Unable to access opcode bytes at 0x36.
Peter, that smells like perhaps either: commit b6c881b248ef ("x86/alternative: Complicate optimize_nops() some more") commit 6c480f222128 ("x86/alternative: Rewrite optimize_nops() some")
So I did find me a 'funny' there, but nothing that explains boot fail.
It would think that 'PAUSE' is a 2 byte NOP and replace it with NOP2; which is not quite the same thing. The below seems to cure that.
Let me continue poking at things...
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 93aa95afd005..bb0a7b03e52f 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -159,9 +160,12 @@ void text_poke_early(void *addr, const void *opcode, size_t len); */ static bool insn_is_nop(struct insn *insn) { - if (insn->opcode.bytes[0] == 0x90) + /* Anything NOP, but not REP NOP. */ + if (insn->opcode.bytes[0] == 0x90 && + (!insn->prefixes.nbytes || insn->prefixes.bytes[0] != 0xF3)) return true;
+ /* NOPL */ if (insn->opcode.bytes[0] == 0x0F && insn->opcode.bytes[1] == 0x1F) return true;
On Wed, May 24, 2023 at 6:01 AM Peter Zijlstra peterz@infradead.org wrote:
On Wed, May 17, 2023 at 11:11:51AM -0700, Nick Desaulniers wrote:
On Wed, May 17, 2023 at 8:21 AM Naresh Kamboju naresh.kamboju@linaro.org wrote:
Linux next-20230517 build with clang nightly for i386 boot fails intermittently.
Keyword: intermittently. That will make tracking this down fun.
Our CI also hit a boot failure on tip/master with the same splat: https://github.com/ClangBuiltLinux/continuous-integration2/actions/runs/4998... Though the CI pulled down a SHA 0932447780e1f9a43bf68ef7fe3d9b41b46d58fc which looks weird on https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=09324...
Notice: this object is not reachable from any branch.
Github isn't willing to show me content unless I log in or somesuch nonsense.
Ah, sorry about that. https://paste.debian.net/1281050/ should be the log of ours. https://storage.tuxsuite.com/public/clangbuiltlinux/continuous-integration2/... is the corresponding build artifact.
There's ongoing discussion in #x86 on LinuxNet. I suspect that a few of Naresh's recent reports are all perhaps one single issue.
Arnd mentioned https://lore.kernel.org/all/CA+G9fYvVZ9WF-2zfrYeo3xnWNra0QGxLzei+b4yANZwEvr5... which looks similar but is with GCC.
Either way, we're seeing this in mainline.
That this failed in -next and -tip in the same way makes me wonder if something affecting this is coming in via -tip? Maybe the splat looks familiar to x86 folks?
I haven't been able to reproduce locally when my machine is relatively load-less. If I do a kernel build in the background, I was able to get QEMU to hang, but without any splat. That was using tip/master @ f81d8f759e7f.
Naresh, when you say "intermittent" do you have any data on the relative frequency of this boot failure? (Also, please make sure to use llvm@lists.linux.dev in the future; we moved mailing lists years ago).
Looks like our CI report linked above has an additional splat though via apply_alternatives and optimize_nops.
[ 0.166742] Code: Unable to access opcode bytes at 0x36.
Peter, that smells like perhaps either: commit b6c881b248ef ("x86/alternative: Complicate optimize_nops() some more") commit 6c480f222128 ("x86/alternative: Rewrite optimize_nops() some")
So I did find me a 'funny' there, but nothing that explains boot fail.
It would think that 'PAUSE' is a 2 byte NOP and replace it with NOP2; which is not quite the same thing. The below seems to cure that.
Let me continue poking at things...
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 93aa95afd005..bb0a7b03e52f 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -159,9 +160,12 @@ void text_poke_early(void *addr, const void *opcode, size_t len); */ static bool insn_is_nop(struct insn *insn) {
if (insn->opcode.bytes[0] == 0x90)
/* Anything NOP, but not REP NOP. */if (insn->opcode.bytes[0] == 0x90 &&(!insn->prefixes.nbytes || insn->prefixes.bytes[0] != 0xF3)) return true;/* NOPL */ if (insn->opcode.bytes[0] == 0x0F && insn->opcode.bytes[1] == 0x1F) return true;
-
Naresh Kamboju -
Nick Desaulniers -
Peter Zijlstra