enable_step_tsk is the only user of disable_dbg, which doesn't respect our 'dai' order for exception masking. enable_step_tsk may enable single-step, so previously needed to mask debug exceptions to prevent us from single-stepping kernel_exit. enable_step_tsk is called at the end of the ret_to_user loop, which has already masked all exceptions so this is no longer needed. Remove disable_dbg, add a comment that enable_step_tsk's caller should have masked debug. Signed-off-by: James Morse <james.morse@xxxxxxx> --- arch/arm64/include/asm/assembler.h | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 114e741ca873..1b0972046a72 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -68,13 +68,6 @@ msr daif, \flags .endm -/* - * Enable and disable debug exceptions. - */ - .macro disable_dbg - msr daifset, #8 - .endm - .macro enable_dbg msr daifclr, #8 .endm @@ -88,9 +81,9 @@ 9990: .endm + /* call with daif masked */ .macro enable_step_tsk, flgs, tmp tbz \flgs, #TIF_SINGLESTEP, 9990f - disable_dbg mrs \tmp, mdscr_el1 orr \tmp, \tmp, #1 msr mdscr_el1, \tmp -- 2.13.3 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
