diff options
| author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2016-09-09 14:07:15 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2016-09-09 15:03:29 +0100 |
| commit | 9dbd5bb25c56e35e6b4c34d968689a1ded850924 (patch) | |
| tree | f81f727180de3d8eef52c1d69d72a46cc196eea5 /arch/arm64/kernel/traps.c | |
| parent | 072f0a633838aca13b5a8b211eb64f5c445cfd7c (diff) | |
arm64: Refactor sysinstr exception handling
Right now we trap some of the user space data cache operations
based on a few Errata (ARM 819472, 826319, 827319 and 824069).
We need to trap userspace access to CTR_EL0, if we detect mismatched
cache line size. Since both these traps share the EC, refactor
the handler a little bit to make it a bit more reader friendly.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/kernel/traps.c')
| -rw-r--r-- | arch/arm64/kernel/traps.c | 73 |
1 files changed, 47 insertions, 26 deletions
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index e04f83873af7..224f64eddd93 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -447,36 +447,29 @@ void cpu_enable_cache_maint_trap(void *__unused) : "=r" (res) \ : "r" (address), "i" (-EFAULT) ) -asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs) +static void user_cache_maint_handler(unsigned int esr, struct pt_regs *regs) { unsigned long address; - int ret; + int rt = (esr & ESR_ELx_SYS64_ISS_RT_MASK) >> ESR_ELx_SYS64_ISS_RT_SHIFT; + int crm = (esr & ESR_ELx_SYS64_ISS_CRM_MASK) >> ESR_ELx_SYS64_ISS_CRM_SHIFT; + int ret = 0; - /* if this is a write with: Op0=1, Op2=1, Op1=3, CRn=7 */ - if ((esr & 0x01fffc01) == 0x0012dc00) { - int rt = (esr >> 5) & 0x1f; - int crm = (esr >> 1) & 0x0f; + address = (rt == 31) ? 0 : regs->regs[rt]; - address = (rt == 31) ? 0 : regs->regs[rt]; - - switch (crm) { - case 11: /* DC CVAU, gets promoted */ - __user_cache_maint("dc civac", address, ret); - break; - case 10: /* DC CVAC, gets promoted */ - __user_cache_maint("dc civac", address, ret); - break; - case 14: /* DC CIVAC */ - __user_cache_maint("dc civac", address, ret); - break; - case 5: /* IC IVAU */ - __user_cache_maint("ic ivau", address, ret); - break; - default: - force_signal_inject(SIGILL, ILL_ILLOPC, regs, 0); - return; - } - } else { + switch (crm) { + case ESR_ELx_SYS64_ISS_CRM_DC_CVAU: /* DC CVAU, gets promoted */ + __user_cache_maint("dc civac", address, ret); + break; + case ESR_ELx_SYS64_ISS_CRM_DC_CVAC: /* DC CVAC, gets promoted */ + __user_cache_maint("dc civac", address, ret); + break; + case ESR_ELx_SYS64_ISS_CRM_DC_CIVAC: /* DC CIVAC */ + __user_cache_maint("dc civac", address, ret); + break; + case ESR_ELx_SYS64_ISS_CRM_IC_IVAU: /* IC IVAU */ + __user_cache_maint("ic ivau", address, ret); + break; + default: force_signal_inject(SIGILL, ILL_ILLOPC, regs, 0); return; } @@ -487,6 +480,34 @@ asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs) regs->pc += 4; } +struct sys64_hook { + unsigned int esr_mask; + unsigned int esr_val; + void (*handler)(unsigned int esr, struct pt_regs *regs); +}; + +static struct sys64_hook sys64_hooks[] = { + { + .esr_mask = ESR_ELx_SYS64_ISS_EL0_CACHE_OP_MASK, + .esr_val = ESR_ELx_SYS64_ISS_EL0_CACHE_OP_VAL, + .handler = user_cache_maint_handler, + }, + {}, +}; + +asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs) +{ + struct sys64_hook *hook; + + for (hook = sys64_hooks; hook->handler; hook++) + if ((hook->esr_mask & esr) == hook->esr_val) { + hook->handler(esr, regs); + return; + } + + force_signal_inject(SIGILL, ILL_ILLOPC, regs, 0); +} + long compat_arm_syscall(struct pt_regs *regs); asmlinkage long do_ni_syscall(struct pt_regs *regs) |