[PATCH 5.19 502/717] powerpc/64: mark irqs hard disabled in boot paca

From: Greg Kroah-Hartman
Date: Sat Oct 22 2022 - 04:25:50 EST


From: Nicholas Piggin <npiggin@xxxxxxxxx>

[ Upstream commit 799f7063c7645f9a751d17f5dfd73b952f962cd2 ]

This prevents interrupts in early boot (e.g., program check) from
enabling MSR[EE], potentially causing endian mismatch or other
crashes when reporting early boot traps.

Fixes: 4423eb5ae32ec ("powerpc/64/interrupt: make normal synchronous interrupts enable MSR[EE] if possible")
Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220926054305.2671436-3-npiggin@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/powerpc/kernel/setup_64.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 5761f08dae95..6562517bcb3b 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -183,8 +183,10 @@ static void __init fixup_boot_paca(void)
get_paca()->cpu_start = 1;
/* Allow percpu accesses to work until we setup percpu data */
get_paca()->data_offset = 0;
- /* Mark interrupts disabled in PACA */
+ /* Mark interrupts soft and hard disabled in PACA */
irq_soft_mask_set(IRQS_DISABLED);
+ get_paca()->irq_happened = PACA_IRQ_HARD_DIS;
+ WARN_ON(mfmsr() & MSR_EE);
}

static void __init configure_exceptions(void)
--
2.35.1