diff options
| author | Lucas Stach <l.stach@pengutronix.de> | 2015-10-19 13:38:09 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-10-19 17:08:33 +0100 |
| commit | 9254970cbbf542a0085e491810f0144a27885702 (patch) | |
| tree | f46c0c1ce8575aecc8133703117a1be5ab181ad1 /arch/arm/mm | |
| parent | c8d46ece44458a2088896d6fcae123a72bdfd429 (diff) | |
ARM: 8447/1: catch pending imprecise abort on unmask
Install a non-faulting handler just before unmasking imprecise aborts
and switch back to the regular one after unmasking is done.
This catches any pending imprecise abort that the firmware/bootloader
may have left behind that would normally crash the kernel at that point.
As there are apparently a lot of bootlaoders out there that do such a
thing it makes sense to handle it in the common startup code.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Tyler Baker <tyler.baker@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mm')
| -rw-r--r-- | arch/arm/mm/fault.c | 22 | ||||
| -rw-r--r-- | arch/arm/mm/fault.h | 1 | ||||
| -rw-r--r-- | arch/arm/mm/mmu.c | 3 |
3 files changed, 25 insertions, 1 deletions
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 0d629b8f973f..daafcf121ce0 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -593,6 +593,28 @@ do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs) arm_notify_die("", regs, &info, ifsr, 0); } +/* + * Abort handler to be used only during first unmasking of asynchronous aborts + * on the boot CPU. This makes sure that the machine will not die if the + * firmware/bootloader left an imprecise abort pending for us to trip over. + */ +static int __init early_abort_handler(unsigned long addr, unsigned int fsr, + struct pt_regs *regs) +{ + pr_warn("Hit pending asynchronous external abort (FSR=0x%08x) during " + "first unmask, this is most likely caused by a " + "firmware/bootloader bug.\n", fsr); + + return 0; +} + +void __init early_abt_enable(void) +{ + fsr_info[22].fn = early_abort_handler; + local_abt_enable(); + fsr_info[22].fn = do_bad; +} + #ifndef CONFIG_ARM_LPAE static int __init exceptions_init(void) { diff --git a/arch/arm/mm/fault.h b/arch/arm/mm/fault.h index cf08bdfbe0d6..05ec5e0df32d 100644 --- a/arch/arm/mm/fault.h +++ b/arch/arm/mm/fault.h @@ -24,5 +24,6 @@ static inline int fsr_fs(unsigned int fsr) void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs); unsigned long search_exception_table(unsigned long addr); +void early_abt_enable(void); #endif /* __ARCH_ARM_FAULT_H */ diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index f65a6f344b6d..4867f5daf82c 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -38,6 +38,7 @@ #include <asm/mach/pci.h> #include <asm/fixmap.h> +#include "fault.h" #include "mm.h" #include "tcm.h" @@ -1365,7 +1366,7 @@ static void __init devicemaps_init(const struct machine_desc *mdesc) flush_cache_all(); /* Enable asynchronous aborts */ - local_abt_enable(); + early_abt_enable(); } static void __init kmap_init(void) |