lkml.org 
[lkml]   [2018]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.14 21/71] ARM: net: bpf: clarify tail_call index
    Date
    4.14-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Russell King <rmk+kernel@armlinux.org.uk>

    commit 091f02483df7b56615b524491f404e574c5e0668 upstream.

    As per 90caccdd8cc0 ("bpf: fix bpf_tail_call() x64 JIT"), the index used
    for array lookup is defined to be 32-bit wide. Update a misleading
    comment that suggests it is 64-bit wide.

    Fixes: 39c13c204bb1 ("arm: eBPF JIT compiler")
    Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    arch/arm/net/bpf_jit_32.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/arch/arm/net/bpf_jit_32.c
    +++ b/arch/arm/net/bpf_jit_32.c
    @@ -1016,7 +1016,7 @@ static int emit_bpf_tail_call(struct jit
    emit_a32_mov_i(tmp[1], off, false, ctx);
    emit(ARM_LDR_I(tmp2[1], ARM_SP, STACK_VAR(r2[1])), ctx);
    emit(ARM_LDR_R(tmp[1], tmp2[1], tmp[1]), ctx);
    - /* index (64 bit) */
    + /* index is 32-bit for arrays */
    emit(ARM_LDR_I(tmp2[1], ARM_SP, STACK_VAR(r3[1])), ctx);
    /* index >= array->map.max_entries */
    emit(ARM_CMP_R(tmp2[1], tmp[1]), ctx);

    \
     
     \ /
      Last update: 2018-01-29 22:03    [W:3.522 / U:0.924 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site