aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/Kconfig
diff options
context:
space:
mode:
authorWill Deacon <will.deacon@arm.com>2012-04-20 17:20:08 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2012-04-23 14:21:52 +0100
commitf0c4b8d653f5ee091fb8d4d02ed7eaad397491bb (patch)
treecc7f1d1be2354dee506453f63f92a878384f30a8 /arch/arm/Kconfig
parente895bd7992df1ebd1e0c28f7965520482bc83b74 (diff)
ARM: 7396/1: errata: only handle ARM erratum #326103 on affected cores
Erratum #326103 ("FSR write bit incorrect on a SWP to read-only memory") only affects the ARM 1136 core prior to r1p0. The workaround disassembles the faulting instruction to determine whether it was a read or write access on all v6 cores. An issue has been reported on the ARM 11MPCore whereby loading the faulting instruction may happen in parallel with that page being unmapped, resulting in a deadlock due to the lack of TLB broadcasting in hardware: http://lists.infradead.org/pipermail/linux-arm-kernel/2012-March/091561.html This patch limits the workaround so that it is only used on affected cores, which are known to be UP only. Other v6 cores can rely on the FSR to indicate the access type correctly. Cc: stable@vger.kernel.org Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/Kconfig')
-rw-r--r--arch/arm/Kconfig9
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index cf006d40342..36586dba6fa 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1186,6 +1186,15 @@ if !MMU
source "arch/arm/Kconfig-nommu"
endif
+config ARM_ERRATA_326103
+ bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
+ depends on CPU_V6
+ help
+ Executing a SWP instruction to read-only memory does not set bit 11
+ of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
+ treat the access as a read, preventing a COW from occurring and
+ causing the faulting task to livelock.
+
config ARM_ERRATA_411920
bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
depends on CPU_V6 || CPU_V6K