diff options
Diffstat (limited to 'arch/arm/kernel/hw_breakpoint.c')
| -rw-r--r-- | arch/arm/kernel/hw_breakpoint.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c index dc0fb7a81371..93f9034e4e72 100644 --- a/arch/arm/kernel/hw_breakpoint.c +++ b/arch/arm/kernel/hw_breakpoint.c @@ -17,6 +17,7 @@ #include <linux/perf_event.h> #include <linux/hw_breakpoint.h> #include <linux/smp.h> +#include <linux/cfi.h> #include <linux/cpu_pm.h> #include <linux/coresight.h> @@ -903,6 +904,37 @@ unlock: watchpoint_single_step_handler(addr); } +#ifdef CONFIG_CFI_CLANG +static void hw_breakpoint_cfi_handler(struct pt_regs *regs) +{ + /* + * TODO: implementing target and type to pass to CFI using the more + * elaborate report_cfi_failure() requires compiler work. To be able + * to properly extract target information the compiler needs to + * emit a stable instructions sequence for the CFI checks so we can + * decode the instructions preceding the trap and figure out which + * registers were used. + */ + + switch (report_cfi_failure_noaddr(regs, instruction_pointer(regs))) { + case BUG_TRAP_TYPE_BUG: + die("Oops - CFI", regs, 0); + break; + case BUG_TRAP_TYPE_WARN: + /* Skip the breaking instruction */ + instruction_pointer(regs) += 4; + break; + default: + die("Unknown CFI error", regs, 0); + break; + } +} +#else +static void hw_breakpoint_cfi_handler(struct pt_regs *regs) +{ +} +#endif + /* * Called from either the Data Abort Handler [watchpoint] or the * Prefetch Abort Handler [breakpoint] with interrupts disabled. @@ -932,6 +964,9 @@ static int hw_breakpoint_pending(unsigned long addr, unsigned int fsr, case ARM_ENTRY_SYNC_WATCHPOINT: watchpoint_handler(addr, fsr, regs); break; + case ARM_ENTRY_CFI_BREAKPOINT: + hw_breakpoint_cfi_handler(regs); + break; default: ret = 1; /* Unhandled fault. */ } |