diff options
Diffstat (limited to 'arch/arm/mm')
| -rw-r--r-- | arch/arm/mm/Kconfig | 14 | ||||
| -rw-r--r-- | arch/arm/mm/abort-ev6.S | 16 | ||||
| -rw-r--r-- | arch/arm/mm/mm-armv.c | 5 |
3 files changed, 33 insertions, 2 deletions
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index 5b670c9ac5ef..007766a0644c 100644 --- a/arch/arm/mm/Kconfig +++ b/arch/arm/mm/Kconfig @@ -409,3 +409,17 @@ config CPU_BPREDICT_DISABLE depends on CPU_ARM1020 help Say Y here to disable branch prediction. If unsure, say N. + +config HAS_TLS_REG + bool + depends on CPU_32v6 && !CPU_32v5 && !CPU_32v4 && !CPU_32v3 + help + This selects support for the CP15 thread register. + It is defined to be available on ARMv6 or later. However + if the kernel is configured to support multiple CPUs including + a pre-ARMv6 processors, or if a given ARMv6 processor doesn't + implement the thread register for some reason, then access to + this register from user space must be trapped and emulated. + If user space is relying on the __kuser_get_tls code then + there should not be any impact. + diff --git a/arch/arm/mm/abort-ev6.S b/arch/arm/mm/abort-ev6.S index 38b2cbb89beb..8f76f3df7b4c 100644 --- a/arch/arm/mm/abort-ev6.S +++ b/arch/arm/mm/abort-ev6.S @@ -1,5 +1,6 @@ #include <linux/linkage.h> #include <asm/assembler.h> +#include "abort-macro.S" /* * Function: v6_early_abort * @@ -13,11 +14,26 @@ * : sp = pointer to registers * * Purpose : obtain information about current aborted instruction. + * Note: we read user space. This means we might cause a data + * abort here if the I-TLB and D-TLB aren't seeing the same + * picture. Unfortunately, this does happen. We live with it. */ .align 5 ENTRY(v6_early_abort) mrc p15, 0, r1, c5, c0, 0 @ get FSR mrc p15, 0, r0, c6, c0, 0 @ get FAR +/* + * Faulty SWP instruction on 1136 doesn't set bit 11 in DFSR. + * The test below covers all the write situations, including Java bytecodes + */ + bic r1, r1, #1 << 11 | 1 << 10 @ clear bits 11 and 10 of FSR + tst r3, #PSR_J_BIT @ Java? + movne pc, lr + do_thumb_abort + ldreq r3, [r2] @ read aborted ARM instruction + do_ldrd_abort + tst r3, #1 << 20 @ L = 0 -> write + orreq r1, r1, #1 << 11 @ yes. mov pc, lr diff --git a/arch/arm/mm/mm-armv.c b/arch/arm/mm/mm-armv.c index f5a87db8b498..585dfb8e20b9 100644 --- a/arch/arm/mm/mm-armv.c +++ b/arch/arm/mm/mm-armv.c @@ -411,9 +411,10 @@ static void __init build_mem_type_table(void) mem_types[MT_MEMORY].prot_sect &= ~PMD_BIT4; mem_types[MT_ROM].prot_sect &= ~PMD_BIT4; /* - * Mark cache clean areas read only from SVC mode - * and no access from userspace. + * Mark cache clean areas and XIP ROM read only + * from SVC mode and no access from userspace. */ + mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE; mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE; mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE; } |