diff options
| -rw-r--r-- | include/linux/sched.h | 4 | ||||
| -rw-r--r-- | kernel/kcsan/core.c | 23 | ||||
| -rw-r--r-- | kernel/kcsan/kcsan.h | 7 | ||||
| -rw-r--r-- | kernel/kcsan/report.c | 3 |
4 files changed, 37 insertions, 0 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index 52e0fdd6a555..060e9214c8b5 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1184,8 +1184,12 @@ struct task_struct { #ifdef CONFIG_KASAN unsigned int kasan_depth; #endif + #ifdef CONFIG_KCSAN struct kcsan_ctx kcsan_ctx; +#ifdef CONFIG_TRACE_IRQFLAGS + struct irqtrace_events kcsan_save_irqtrace; +#endif #endif #ifdef CONFIG_FUNCTION_GRAPH_TRACER diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c index 732623c30359..0fe068192781 100644 --- a/kernel/kcsan/core.c +++ b/kernel/kcsan/core.c @@ -291,6 +291,20 @@ static inline unsigned int get_delay(void) 0); } +void kcsan_save_irqtrace(struct task_struct *task) +{ +#ifdef CONFIG_TRACE_IRQFLAGS + task->kcsan_save_irqtrace = task->irqtrace; +#endif +} + +void kcsan_restore_irqtrace(struct task_struct *task) +{ +#ifdef CONFIG_TRACE_IRQFLAGS + task->irqtrace = task->kcsan_save_irqtrace; +#endif +} + /* * Pull everything together: check_access() below contains the performance * critical operations; the fast-path (including check_access) functions should @@ -336,9 +350,11 @@ static noinline void kcsan_found_watchpoint(const volatile void *ptr, flags = user_access_save(); if (consumed) { + kcsan_save_irqtrace(current); kcsan_report(ptr, size, type, KCSAN_VALUE_CHANGE_MAYBE, KCSAN_REPORT_CONSUMED_WATCHPOINT, watchpoint - watchpoints); + kcsan_restore_irqtrace(current); } else { /* * The other thread may not print any diagnostics, as it has @@ -396,6 +412,12 @@ kcsan_setup_watchpoint(const volatile void *ptr, size_t size, int type) goto out; } + /* + * Save and restore the IRQ state trace touched by KCSAN, since KCSAN's + * runtime is entered for every memory access, and potentially useful + * information is lost if dirtied by KCSAN. + */ + kcsan_save_irqtrace(current); if (!kcsan_interrupt_watcher) local_irq_save(irq_flags); @@ -539,6 +561,7 @@ kcsan_setup_watchpoint(const volatile void *ptr, size_t size, int type) out_unlock: if (!kcsan_interrupt_watcher) local_irq_restore(irq_flags); + kcsan_restore_irqtrace(current); out: user_access_restore(ua_flags); } diff --git a/kernel/kcsan/kcsan.h b/kernel/kcsan/kcsan.h index 763d6d08d94b..29480010dc30 100644 --- a/kernel/kcsan/kcsan.h +++ b/kernel/kcsan/kcsan.h @@ -9,6 +9,7 @@ #define _KERNEL_KCSAN_KCSAN_H #include <linux/kcsan.h> +#include <linux/sched.h> /* The number of adjacent watchpoints to check. */ #define KCSAN_CHECK_ADJACENT 1 @@ -23,6 +24,12 @@ extern unsigned int kcsan_udelay_interrupt; extern bool kcsan_enabled; /* + * Save/restore IRQ flags state trace dirtied by KCSAN. + */ +void kcsan_save_irqtrace(struct task_struct *task); +void kcsan_restore_irqtrace(struct task_struct *task); + +/* * Initialize debugfs file. */ void kcsan_debugfs_init(void); diff --git a/kernel/kcsan/report.c b/kernel/kcsan/report.c index 6b2fb1a6d8cd..9d07e175de0f 100644 --- a/kernel/kcsan/report.c +++ b/kernel/kcsan/report.c @@ -308,6 +308,9 @@ static void print_verbose_info(struct task_struct *task) if (!task) return; + /* Restore IRQ state trace for printing. */ + kcsan_restore_irqtrace(task); + pr_err("\n"); debug_show_held_locks(task); print_irqtrace_events(task); |