arm64: Lower priority mask for GIC_PRIO_IRQON

On a system with two security states, if SCR_EL3.FIQ is cleared,
non-secure IRQ priorities get shifted to fit the secure view but
priority masks aren't.

On such system, it turns out that GIC_PRIO_IRQON masks the priority of
normal interrupts, which obviously ends up in a hang.

Increase GIC_PRIO_IRQON value (i.e. lower priority) to make sure
interrupts are not blocked by it.

Cc: Oleg Nesterov <oleg@redhat.com>
Fixes: bd82d4bd21 ("arm64: Fix incorrect irqflag restore for priority masking")
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Julien Thierry <julien.thierry.kdev@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
[will: fixed Fixes: tag]
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Julien Thierry 2019-07-29 15:57:46 +01:00 committed by Will Deacon
parent f1d4836201
commit 677379bc91
2 changed files with 7 additions and 1 deletions

View File

@ -155,6 +155,12 @@ static inline void gic_pmr_mask_irqs(void)
BUILD_BUG_ON(GICD_INT_DEF_PRI < (GIC_PRIO_IRQOFF |
GIC_PRIO_PSR_I_SET));
BUILD_BUG_ON(GICD_INT_DEF_PRI >= GIC_PRIO_IRQON);
/*
* Need to make sure IRQON allows IRQs when SCR_EL3.FIQ is cleared
* and non-secure PMR accesses are not subject to the shifts that
* are applied to IRQ priorities
*/
BUILD_BUG_ON((0x80 | (GICD_INT_DEF_PRI >> 1)) >= GIC_PRIO_IRQON);
gic_write_pmr(GIC_PRIO_IRQOFF);
}

View File

@ -30,7 +30,7 @@
* in the the priority mask, it indicates that PSR.I should be set and
* interrupt disabling temporarily does not rely on IRQ priorities.
*/
#define GIC_PRIO_IRQON 0xc0
#define GIC_PRIO_IRQON 0xe0
#define GIC_PRIO_IRQOFF (GIC_PRIO_IRQON & ~0x80)
#define GIC_PRIO_PSR_I_SET (1 << 4)