arm64: Do not enable IRQs for ct_user_exit
authorJulien Thierry <julien.thierry@arm.com>
Tue, 11 Jun 2019 09:38:06 +0000 (10:38 +0100)
committerCatalin Marinas <catalin.marinas@arm.com>
Fri, 21 Jun 2019 10:19:12 +0000 (11:19 +0100)
For el0_dbg and el0_error, DAIF bits get explicitly cleared before
calling ct_user_exit.

When context tracking is disabled, DAIF gets set (almost) immediately
after. When context tracking is enabled, among the first things done
is disabling IRQs.

What is actually needed is:
- PSR.D = 0 so the system can be debugged (should be already the case)
- PSR.A = 0 so async error can be handled during context tracking

Do not clear PSR.I in those two locations.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arch/arm64/kernel/entry.S

index cd0c7af..89ab6bd 100644 (file)
@@ -870,7 +870,7 @@ el0_dbg:
        mov     x1, x25
        mov     x2, sp
        bl      do_debug_exception
-       enable_daif
+       enable_da_f
        ct_user_exit
        b       ret_to_user
 el0_inv:
@@ -922,7 +922,7 @@ el0_error_naked:
        enable_dbg
        mov     x0, sp
        bl      do_serror
-       enable_daif
+       enable_da_f
        ct_user_exit
        b       ret_to_user
 ENDPROC(el0_error)