Re: [paulmck-rcu:dev.2024.07.17a] [EXP rcuscale] 9e146da3f3: WARNING:at_lib/alloc_tag.c:#alloc_tag_module_unload
From: Paul E. McKenney
Date: Sun Jul 28 2024 - 12:34:51 EST
On Thu, Jul 25, 2024 at 02:49:28PM +0800, kernel test robot wrote:
>
> hi, Paul E. McKenney,
>
> we noticed in commit message "Not for mainline in its current form".
>
> we saw below commits in the branch:
> cdd5ddaa17fe fixup! EXP rcuscale: Dump debug info
> 4f60b8b679fd squash! EXP rcuscale: Dump debug info
>
> but we still observed same issue on the branch tip:
> fe09f037acf7 (dev.2024.07.17a) rcuscale: Make rcu_scale_writer() tolerate repeated GFP_KERNEL failure
>
> at the same time, we noticed there is no same title commit in newer branch:
> dev.2024.07.18a
>
> just still made below formal report to you since we are not sure if it could
> supply any useful information. if not, please just ignore. Thanks!
I believe that I have fixed this in the current "dev" branch by fusing
a half-fix with the remainder of the fix. Please let me know if I am
mistaken, and thank you for your testing work!
Thanx, Paul
> Hello,
>
> kernel test robot noticed "WARNING:at_lib/alloc_tag.c:#alloc_tag_module_unload" on:
>
> commit: 9e146da3f351c0eaf66756cc3a6c6a5845b81187 ("EXP rcuscale: Dump debug info")
> https://git.kernel.org/cgit/linux/kernel/git/paulmck/linux-rcu.git dev.2024.07.17a
>
> in testcase: rcuscale
> version:
> with following parameters:
>
> runtime: 300s
> scale_type: tasks-tracing
>
>
>
> compiler: gcc-13
> test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -m 4G
>
> (please refer to attached dmesg/kmsg for entire log/backtrace)
>
>
> +-----------------------------------------------------+------------+------------+
> | | e136892a8e | 9e146da3f3 |
> +-----------------------------------------------------+------------+------------+
> | WARNING:at_lib/alloc_tag.c:#alloc_tag_module_unload | 0 | 12 |
> | EIP:alloc_tag_module_unload | 0 | 12 |
> +-----------------------------------------------------+------------+------------+
>
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@xxxxxxxxx>
> | Closes: https://lore.kernel.org/oe-lkp/202407251351.f65c33a0-lkp@xxxxxxxxx
>
>
> [ 439.356638][ T1799] ------------[ cut here ]------------
> [ 439.357183][ T1799] kernel/rcu/rcuscale.c:1037 module rcuscale func:rcu_scale_init has 8 allocated at module unload
> [ 439.357225][ T1799] WARNING: CPU: 0 PID: 1799 at lib/alloc_tag.c:168 alloc_tag_module_unload (lib/alloc_tag.c:168 (discriminator 1))
> [ 439.358903][ T1799] Modules linked in: rcuscale(-) torture [last unloaded: rcuscale]
> [ 439.359632][ T1799] CPU: 0 PID: 1799 Comm: rmmod Not tainted 6.10.0-rc5-00110-g9e146da3f351 #1 308a8ed8688556473cf6c28b678fa76bc00dc1d7
> [ 439.360679][ T1799] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
> [ 439.361546][ T1799] EIP: alloc_tag_module_unload (lib/alloc_tag.c:168 (discriminator 1))
> [ 439.361993][ T1799] Code: 92 ff ff ff 8b 55 e8 8b 45 e4 85 d2 75 04 85 c0 74 21 52 50 ff 73 0c ff 73 08 ff 73 04 ff 73 10 68 d8 2f cb c2 e8 ec 39 9f ff <0f> 0b c6 45 d3 00 83 c4 1c 8d 45 d4 e8 2e fc ff ff 89 c3 eb b2 8a
> All code
> ========
> 0: 92 xchg %eax,%edx
> 1: ff (bad)
> 2: ff (bad)
> 3: ff 8b 55 e8 8b 45 decl 0x458be855(%rbx)
> 9: e4 85 in $0x85,%al
> b: d2 75 04 shlb %cl,0x4(%rbp)
> e: 85 c0 test %eax,%eax
> 10: 74 21 je 0x33
> 12: 52 push %rdx
> 13: 50 push %rax
> 14: ff 73 0c push 0xc(%rbx)
> 17: ff 73 08 push 0x8(%rbx)
> 1a: ff 73 04 push 0x4(%rbx)
> 1d: ff 73 10 push 0x10(%rbx)
> 20: 68 d8 2f cb c2 push $0xffffffffc2cb2fd8
> 25: e8 ec 39 9f ff call 0xffffffffff9f3a16
> 2a:* 0f 0b ud2 <-- trapping instruction
> 2c: c6 45 d3 00 movb $0x0,-0x2d(%rbp)
> 30: 83 c4 1c add $0x1c,%esp
> 33: 8d 45 d4 lea -0x2c(%rbp),%eax
> 36: e8 2e fc ff ff call 0xfffffffffffffc69
> 3b: 89 c3 mov %eax,%ebx
> 3d: eb b2 jmp 0xfffffffffffffff1
> 3f: 8a .byte 0x8a
>
> Code starting with the faulting instruction
> ===========================================
> 0: 0f 0b ud2
> 2: c6 45 d3 00 movb $0x0,-0x2d(%rbp)
> 6: 83 c4 1c add $0x1c,%esp
> 9: 8d 45 d4 lea -0x2c(%rbp),%eax
> c: e8 2e fc ff ff call 0xfffffffffffffc3f
> 11: 89 c3 mov %eax,%ebx
> 13: eb b2 jmp 0xffffffffffffffc7
> 15: 8a .byte 0x8a
> [ 439.363599][ T1799] EAX: 00000000 EBX: efbf9040 ECX: 00000000 EDX: 00000000
> [ 439.364218][ T1799] ESI: c4215290 EDI: ebdfdedc EBP: ebdfdee8 ESP: ebdfde9c
> [ 439.364818][ T1799] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 EFLAGS: 00210246
> [ 439.365471][ T1799] CR0: 80050033 CR2: b71fd210 CR3: 04026300 CR4: 000406b0
> [ 439.366083][ T1799] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
> [ 439.366676][ T1799] DR6: fffe0ff0 DR7: 00000400
> [ 439.367170][ T1799] Call Trace:
> [ 439.367451][ T1799] ? show_regs (arch/x86/kernel/dumpstack.c:479 arch/x86/kernel/dumpstack.c:465)
> [ 439.367803][ T1799] ? alloc_tag_module_unload (lib/alloc_tag.c:168 (discriminator 1))
> [ 439.368264][ T1799] ? __warn (kernel/panic.c:693)
> [ 439.368604][ T1799] ? report_bug (lib/bug.c:201 lib/bug.c:219)
> [ 439.368992][ T1799] ? alloc_tag_module_unload (lib/alloc_tag.c:168 (discriminator 1))
> [ 439.369435][ T1799] ? exc_overflow (arch/x86/kernel/traps.c:252)
> [ 439.369807][ T1799] ? handle_bug (arch/x86/kernel/traps.c:239)
> [ 439.370162][ T1799] ? exc_invalid_op (arch/x86/kernel/traps.c:260 (discriminator 1))
> [ 439.370549][ T1799] ? handle_exception (arch/x86/entry/entry_32.S:1047)
> [ 439.371024][ T1799] ? exc_overflow (arch/x86/kernel/traps.c:252)
> [ 439.371397][ T1799] ? alloc_tag_module_unload (lib/alloc_tag.c:168 (discriminator 1))
> [ 439.371843][ T1799] ? exc_overflow (arch/x86/kernel/traps.c:252)
> [ 439.372238][ T1799] ? alloc_tag_module_unload (lib/alloc_tag.c:168 (discriminator 1))
> [ 439.372693][ T1799] codetag_unload_module (lib/codetag.c:238 (discriminator 1))
> [ 439.373112][ T1799] free_module (kernel/module/main.c:1266)
> [ 439.373470][ T1799] __do_sys_delete_module+0x1b9/0x206
> [ 439.373968][ T1799] __ia32_sys_delete_module (kernel/module/main.c:700)
> [ 439.374397][ T1799] ia32_sys_call (kbuild/obj/consumer/i386-randconfig-061-20240719/./arch/x86/include/generated/asm/syscalls_32.h:130)
> [ 439.374780][ T1799] do_int80_syscall_32 (arch/x86/entry/common.c:165 (discriminator 1) arch/x86/entry/common.c:339 (discriminator 1))
> [ 439.375225][ T1799] entry_INT80_32 (arch/x86/entry/entry_32.S:944)
> [ 439.375611][ T1799] EIP: 0xb7f79092
> [ 439.375910][ T1799] Code: 00 00 00 e9 90 ff ff ff ff a3 24 00 00 00 68 30 00 00 00 e9 80 ff ff ff ff a3 f8 ff ff ff 66 90 00 00 00 00 00 00 00 00 cd 80 <c3> 8d b4 26 00 00 00 00 8d b6 00 00 00 00 8b 1c 24 c3 8d b4 26 00
> All code
> ========
> 0: 00 00 add %al,(%rax)
> 2: 00 e9 add %ch,%cl
> 4: 90 nop
> 5: ff (bad)
> 6: ff (bad)
> 7: ff (bad)
> 8: ff a3 24 00 00 00 jmp *0x24(%rbx)
> e: 68 30 00 00 00 push $0x30
> 13: e9 80 ff ff ff jmp 0xffffffffffffff98
> 18: ff a3 f8 ff ff ff jmp *-0x8(%rbx)
> 1e: 66 90 xchg %ax,%ax
> ...
> 28: cd 80 int $0x80
> 2a:* c3 ret <-- trapping instruction
> 2b: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi
> 32: 8d b6 00 00 00 00 lea 0x0(%rsi),%esi
> 38: 8b 1c 24 mov (%rsp),%ebx
> 3b: c3 ret
> 3c: 8d .byte 0x8d
> 3d: b4 26 mov $0x26,%ah
> ...
>
> Code starting with the faulting instruction
> ===========================================
> 0: c3 ret
> 1: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi
> 8: 8d b6 00 00 00 00 lea 0x0(%rsi),%esi
> e: 8b 1c 24 mov (%rsp),%ebx
> 11: c3 ret
> 12: 8d .byte 0x8d
> 13: b4 26 mov $0x26,%ah
> ...
> [ 439.377475][ T1799] EAX: ffffffda EBX: 00e4333c ECX: 00000800 EDX: 00484939
> [ 439.378043][ T1799] ESI: 00e43300 EDI: 00e43300 EBP: bfbcdc46 ESP: bfbcccc4
> [ 439.378610][ T1799] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00200202
> [ 439.379237][ T1799] irq event stamp: 5473
> [ 439.379574][ T1799] hardirqs last enabled at (5483): console_unlock (arch/x86/include/asm/irqflags.h:42 arch/x86/include/asm/irqflags.h:77 arch/x86/include/asm/irqflags.h:135 kernel/printk/printk.c:341 kernel/printk/printk.c:2746 kernel/printk/printk.c:3065)
> [ 439.380336][ T1799] hardirqs last disabled at (5494): console_unlock (kernel/printk/printk.c:339 (discriminator 3) kernel/printk/printk.c:2746 (discriminator 3) kernel/printk/printk.c:3065 (discriminator 3))
> [ 439.381023][ T1799] softirqs last enabled at (5142): handle_softirqs (kernel/softirq.c:401 (discriminator 2) kernel/softirq.c:582 (discriminator 2))
> [ 439.381726][ T1799] softirqs last disabled at (5133): __do_softirq (kernel/softirq.c:589)
> [ 439.382384][ T1799] ---[ end trace 0000000000000000 ]---
>
>
>
> The kernel config and materials to reproduce are available at:
> https://download.01.org/0day-ci/archive/20240725/202407251351.f65c33a0-lkp@xxxxxxxxx
>
>
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki
>