[PATCH AUTOSEL 5.3 26/89] arm64: Fix incorrect irqflag restore for priority masking for compat

From: Sasha Levin
Date: Fri Oct 18 2019 - 18:27:06 EST


From: James Morse <james.morse@xxxxxxx>

[ Upstream commit f46f27a576cc3b1e3d45ea50bc06287aa46b04b2 ]

Commit bd82d4bd2188 ("arm64: Fix incorrect irqflag restore for priority
masking") added a macro to the entry.S call paths that leave the
PSTATE.I bit set. This tells the pPNMI masking logic that interrupts
are masked by the CPU, not by the PMR. This value is read back by
local_daif_save().

Commit bd82d4bd2188 added this call to el0_svc, as el0_svc_handler
is called with interrupts masked. el0_svc_compat was missed, but should
be covered in the same way as both of these paths end up in
el0_svc_common(), which expects to unmask interrupts.

Fixes: bd82d4bd2188 ("arm64: Fix incorrect irqflag restore for priority masking")
Signed-off-by: James Morse <james.morse@xxxxxxx>
Cc: Julien Thierry <julien.thierry.kdev@xxxxxxxxx>
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm64/kernel/entry.S | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 84a822748c84e..e304fe04b098d 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -775,6 +775,7 @@ el0_sync_compat:
b.ge el0_dbg
b el0_inv
el0_svc_compat:
+ gic_prio_kentry_setup tmp=x1
mov x0, sp
bl el0_svc_compat_handler
b ret_to_user
--
2.20.1