| Message ID | 1559813517-41540-2-git-send-email-julien.thierry@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: IRQ priority masking and Pseudo-NMI fixes | expand |
Hi Julien, On 06/06/2019 10:31, Julien Thierry wrote: > 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. (last time I looked at this I wrongly assumed ct_user_exit() should be run with interrupts masked, but that isn't what you're saying). Reviewed-by: James Morse <james.morse@arm.com> Thanks, James
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index cd0c7af..89ab6bd 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -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)
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. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Cc:Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> --- arch/arm64/kernel/entry.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 1.9.1