[PATCH v5 06/27] arm64: Delay daif masking for user return
From: Julien Thierry <hidden>
Date: 2018-08-28 15:52:06
Also in:
lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
Masking daif flags is done very early before returning to EL0. Only toggle the interrupt masking while in the vector entry and mask daif once in kernel_exit. Signed-off-by: Julien Thierry <redacted> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <redacted> Cc: Mark Rutland <mark.rutland@arm.com> Cc: James Morse <james.morse@arm.com> --- arch/arm64/kernel/entry.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 09dbea22..85ce06ac 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S@@ -259,9 +259,9 @@ alternative_else_nop_endif .endm .macro kernel_exit, el - .if \el != 0 disable_daif + .if \el != 0 /* Restore the task's original addr_limit. */ ldr x20, [sp, #S_ORIG_ADDR_LIMIT] str x20, [tsk, #TSK_TI_ADDR_LIMIT]
@@ -896,7 +896,7 @@ work_pending: * "slow" syscall return path. */ ret_to_user: - disable_daif + disable_irq // disable interrupts ldr x1, [tsk, #TSK_TI_FLAGS] and x2, x1, #_TIF_WORK_MASK cbnz x2, work_pending
--
1.9.1