Re: [f2fs-dev] [PATCH v2 1/2] f2fs: fix the assign logic of iocb

[Chao Yu]

On 2022/10/27 17:12, Mukesh Ojha wrote:
> commit 18ae8d12991b ("f2fs: show more DIO information in tracepoint")
> introduces iocb field in 'f2fs_direct_IO_enter' trace event
> And it only assigns the pointer and later it accesses its field
> in trace print log.
>
> Unable to handle kernel paging request at virtual address ffffffc04cef3d30
> Mem abort info:
> ESR = 0x96000007
> EC = 0x25: DABT (current EL), IL = 32 bits
>
>   pc : trace_raw_output_f2fs_direct_IO_enter+0x54/0xa4
>   lr : trace_raw_output_f2fs_direct_IO_enter+0x2c/0xa4
>   sp : ffffffc0443cbbd0
>   x29: ffffffc0443cbbf0 x28: ffffff8935b120d0 x27: ffffff8935b12108
>   x26: ffffff8935b120f0 x25: ffffff8935b12100 x24: ffffff8935b110c0
>   x23: ffffff8935b10000 x22: ffffff88859a936c x21: ffffff88859a936c
>   x20: ffffff8935b110c0 x19: ffffff8935b10000 x18: ffffffc03b195060
>   x17: ffffff8935b11e76 x16: 00000000000000cc x15: ffffffef855c4f2c
>   x14: 0000000000000001 x13: 000000000000004e x12: ffff0000ffffff00
>   x11: ffffffef86c350d0 x10: 00000000000010c0 x9 : 000000000fe0002c
>   x8 : ffffffc04cef3d28 x7 : 7f7f7f7f7f7f7f7f x6 : 0000000002000000
>   x5 : ffffff8935b11e9a x4 : 0000000000006250 x3 : ffff0a00ffffff04
>   x2 : 0000000000000002 x1 : ffffffef86a0a31f x0 : ffffff8935b10000
>   Call trace:
>    trace_raw_output_f2fs_direct_IO_enter+0x54/0xa4
>    print_trace_fmt+0x9c/0x138
>    print_trace_line+0x154/0x254
>    tracing_read_pipe+0x21c/0x380
>    vfs_read+0x108/0x3ac
>    ksys_read+0x7c/0xec
>    __arm64_sys_read+0x20/0x30
>    invoke_syscall+0x60/0x150
>    el0_svc_common.llvm.1237943816091755067+0xb8/0xf8
>    do_el0_svc+0x28/0xa0
>
> Fix it by copying the required variables for printing and while at
> it fix the similar issue at some other places in the same file.
>
> Fixes: 18ae8d12991b ("f2fs: show more DIO information in tracepoint")
> Signed-off-by: Mukesh Ojha <quic_mojha@xxxxxxxxxxx>

Reviewed-by: Chao Yu <chao@xxxxxxxxxx>

Thanks,