Provide two debug helpers: - ksw_watch_show(): print the current watch target address and length. - ksw_watch_fire(): intentionally trigger the watchpoint immediately by writing to the watched address, useful for testing HWBP behavior.
Signed-off-by: Jinchao Wang <[email protected]> --- include/linux/kstackwatch.h | 2 ++ mm/kstackwatch/watch.c | 34 ++++++++++++++++++++++++++++++++++ 2 files changed, 36 insertions(+) diff --git a/include/linux/kstackwatch.h b/include/linux/kstackwatch.h index ce3882acc5dc..6daded932ba6 100644 --- a/include/linux/kstackwatch.h +++ b/include/linux/kstackwatch.h @@ -60,5 +60,7 @@ void ksw_watch_exit(void); int ksw_watch_get(struct ksw_watchpoint **out_wp); int ksw_watch_on(struct ksw_watchpoint *wp, ulong watch_addr, u16 watch_len); int ksw_watch_off(struct ksw_watchpoint *wp); +void ksw_watch_show(void); +void ksw_watch_fire(void); #endif /* _KSTACKWATCH_H */ diff --git a/mm/kstackwatch/watch.c b/mm/kstackwatch/watch.c index c2aa912bf4c4..a298c31848a2 100644 --- a/mm/kstackwatch/watch.c +++ b/mm/kstackwatch/watch.c @@ -273,3 +273,37 @@ void ksw_watch_exit(void) { ksw_watch_free(); } + +/* self debug function */ +void ksw_watch_show(void) +{ + struct ksw_watchpoint *wp = current->ksw_ctx.wp; + + if (!wp) { + pr_info("nothing to show\n"); + return; + } + + pr_info("watch target bp_addr: 0x%llx len:%llu\n", wp->attr.bp_addr, + wp->attr.bp_len); +} +EXPORT_SYMBOL_GPL(ksw_watch_show); + +/* self debug function */ +void ksw_watch_fire(void) +{ + struct ksw_watchpoint *wp; + char *ptr; + + wp = current->ksw_ctx.wp; + + if (!wp) { + pr_info("nothing to fire\n"); + return; + } + + ptr = (char *)wp->attr.bp_addr; + pr_warn("watch triggered immediately\n"); + *ptr = 0x42; // This should trigger immediately for any bp_len +} +EXPORT_SYMBOL_GPL(ksw_watch_fire); -- 2.43.0
