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| author | Vincenzo Frascino <vincenzo.frascino@arm.com> | 2019-09-16 11:51:17 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-09-04 12:46:06 +0100 |
| commit | 637ec831ea4f09c7529ac4078399ce4e25b46341 (patch) | |
| tree | 7f8a21f46e15ffc6958c46a202ab8d578b23fb9c /arch/arm64/kernel/process.c | |
| parent | 74f1082487feb90bbf880af14beb8e29c3030c9f (diff) | |
| download | linux-stable-637ec831ea4f09c7529ac4078399ce4e25b46341.tar.gz linux-stable-637ec831ea4f09c7529ac4078399ce4e25b46341.tar.bz2 linux-stable-637ec831ea4f09c7529ac4078399ce4e25b46341.zip | |
arm64: mte: Handle synchronous and asynchronous tag check faults
The Memory Tagging Extension has two modes of notifying a tag check
fault at EL0, configurable through the SCTLR_EL1.TCF0 field:
1. Synchronous raising of a Data Abort exception with DFSC 17.
2. Asynchronous setting of a cumulative bit in TFSRE0_EL1.
Add the exception handler for the synchronous exception and handling of
the asynchronous TFSRE0_EL1.TF0 bit setting via a new TIF flag in
do_notify_resume().
On a tag check failure in user-space, whether synchronous or
asynchronous, a SIGSEGV will be raised on the faulting thread.
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Co-developed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/kernel/process.c')
| -rw-r--r-- | arch/arm64/kernel/process.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index f1804496b935..a49028efab68 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -52,6 +52,7 @@ #include <asm/exec.h> #include <asm/fpsimd.h> #include <asm/mmu_context.h> +#include <asm/mte.h> #include <asm/processor.h> #include <asm/pointer_auth.h> #include <asm/stacktrace.h> @@ -239,7 +240,7 @@ static void print_pstate(struct pt_regs *regs) const char *btype_str = btypes[(pstate & PSR_BTYPE_MASK) >> PSR_BTYPE_SHIFT]; - printk("pstate: %08llx (%c%c%c%c %c%c%c%c %cPAN %cUAO BTYPE=%s)\n", + printk("pstate: %08llx (%c%c%c%c %c%c%c%c %cPAN %cUAO %cTCO BTYPE=%s)\n", pstate, pstate & PSR_N_BIT ? 'N' : 'n', pstate & PSR_Z_BIT ? 'Z' : 'z', @@ -251,6 +252,7 @@ static void print_pstate(struct pt_regs *regs) pstate & PSR_F_BIT ? 'F' : 'f', pstate & PSR_PAN_BIT ? '+' : '-', pstate & PSR_UAO_BIT ? '+' : '-', + pstate & PSR_TCO_BIT ? '+' : '-', btype_str); } } @@ -336,6 +338,7 @@ void flush_thread(void) tls_thread_flush(); flush_ptrace_hw_breakpoint(current); flush_tagged_addr_state(); + flush_mte_state(); } void release_thread(struct task_struct *dead_task) @@ -368,6 +371,9 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) dst->thread.sve_state = NULL; clear_tsk_thread_flag(dst, TIF_SVE); + /* clear any pending asynchronous tag fault raised by the parent */ + clear_tsk_thread_flag(dst, TIF_MTE_ASYNC_FAULT); + return 0; } |