From 84d0fb1bb6257d5d5d45f5e3554ab441b4ff5a74 Mon Sep 17 00:00:00 2001 From: James Morse Date: Thu, 2 Nov 2017 12:12:38 +0000 Subject: arm64: entry.S: Remove disable_dbg 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 Reviewed-by: Julien Thierry Reviewed-by: Catalin Marinas Signed-off-by: Will Deacon --- arch/arm64/include/asm/assembler.h | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) (limited to 'arch/arm64/include') diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index a4aa22241dd1..8bc63fc98752 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -69,13 +69,6 @@ msr daif, \flags .endm -/* - * Enable and disable debug exceptions. - */ - .macro disable_dbg - msr daifset, #8 - .endm - .macro enable_dbg msr daifclr, #8 .endm @@ -89,9 +82,9 @@ 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, #DBG_MDSCR_SS msr mdscr_el1, \tmp -- cgit