From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 161912EA174 for ; Thu, 9 Oct 2025 10:58:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760007493; cv=none; b=XLpydWpwaLAtwfRGcxylRI8CbiivqDi8RSdRkVRjIfVAiR0wU02vjBFdpG6QkQaa1HVJHXvZr5MJUIIlZeezz6Yz1ehxbEjJfzC00ExlFBilo0bxtnoziguzi0uqMH9OGrmV7/OMCcOC1ZqtBVrxvGrXP+4My6vjxI2iy2KAWy0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760007493; c=relaxed/simple; bh=zgbvGJBSx4YBKNkqO/qzz/La9XfnZ3vAatfFaQMoL7I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=b86clgGjZKvnyaQ6/uWEn/b3KZW/fnrnOLbAKbJ9TsC6wx0Y8nDYlHrJTzrKWbWvquvuTlfICspUQ9OeeLxsan3hBni/QbHX3G4Tm00STdrsilSaIPG5dkzzqEHY2PGo/ndWA+HFHcG3OYhd1D23E04IJgjBbcW+Q21h9GEwJys= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=dqecCbLb; arc=none smtp.client-ip=209.85.214.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="dqecCbLb" Received: by mail-pl1-f169.google.com with SMTP id d9443c01a7336-267f0fe72a1so6095015ad.2 for ; Thu, 09 Oct 2025 03:58:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1760007491; x=1760612291; darn=lists.linux.dev; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=UmaGbmiuxIsK0xKTEWJ/f7gfwC2bw8p0SOLh4b9Z4FY=; b=dqecCbLbgHZ5I2QZLzcP14KGc3BA41oOI82WDTooUE50HxdsjAuFnBYl+LSMMDAy5w Ok3UoVJScyk5roQpvS0HMJ414n6lSD5P13qiJpJuBaoj+6QwNnWWvBaiRshUEXyRUSgL Zomwf4AmsTRJkUXpsZuvoYZm7QYSBPV0EBVGqw+nDSbFRzBrhzTjAnSrELyAfiNSIGVS IVdGaEqi6SoA2RDd6J4ZSSY6EbmHq3b7Rjkn3Jk+YeysWIfrKJR7Cz69aoGdfbyXBVGQ yaWXwox4wyMiTFJndveDntW9Yj8213ctantKLXIJG2UxHlQh13AZ4m5BBDUK0U+QLHmX 70sw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1760007491; x=1760612291; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=UmaGbmiuxIsK0xKTEWJ/f7gfwC2bw8p0SOLh4b9Z4FY=; b=qYBwj/5MNdO6gmzqtpbDKscQZC5YGGzDJr71m2HvoF29ERTWMXWVTFJbE2NxrCQbIA ISCblsaYViTe72VHcMuYzR3nAMTb2ypXbmfOLEv16kceq0m49uQz3DwaVDpZiiV16epM zOWrVxS0gkoSWkvoroDZgwoLoGGscwBAs9hESw+n+hrv2kg3XZSaf/1urFp1QVBvZXVJ w1Jv/8gya3dMBxFj4KDivP7fldVxFhkV4Mf1HH8L02sRCGtcUnF0YkJ6R2c77D0z6qea xlNpXINuOkLnU+oZL4zX5LNCRX1qgQ+XeXJpOnN3WNxE+0P4RVVz638VA4Q4l9FdHBaD 5e3w== X-Forwarded-Encrypted: i=1; AJvYcCVPeM0QteQkD4t4Upp9FvTCqy8CgXLizYuQWZWXJJ64d2eM+QeKQQQ57cM0Ricmn3xi3NX6@lists.linux.dev X-Gm-Message-State: AOJu0YzayVJLZ9liO0tZRHuu0boQ45bZak4UgM++PXKf2tyhvLoReSLa H2SqB6heASX+CEVoriXW4zwve6JCeyuXPF/KqRVDOviDYK7hP0WVAzyM X-Gm-Gg: ASbGnctohgMYLvrdDxO4HH+pT/okT+oxw421Z5IAAas+a51jX2BXYei61uTl2Q5CUvE 9hTwFtPlbvCJ1eLtkawx4JbhFgZBuHMrAhikidMPdpfiUxwl9nhswZ4cBi1FpVgeWLnrcZPy1g7 Ga4srKZzq+v9pLO1HOIL64VAlBaS++/ORWyYUpAQo0YYyIEYGS8Ojm0plbfgXXKmYTKjzE/GTVW kdCZ0doFnGNuZBzpR037sANKhIHSjNmCIAmCoxZ4HLi1mvcLj/mWEWnSz/53IgiheuFUiYjysRh w+FDQXnImLGi9WFiroDWYv7Sev2CwqPQiGR6pqgK70dwoO92CSPVZadxlKKEe9DIsoY5M3IVoh7 EJ/yd6TbeRb+VLlF0rADioh6MZtM2ZSgQVanWPDHyyoz6foW584GfEkILyrOT X-Google-Smtp-Source: AGHT+IE5mYvqRuQZ+u7IQ0srPI8O6QG8ywmWS1iS+UAE48zG0ZozJL4ZlmLiRWALZX5JRbD2vynFcw== X-Received: by 2002:a17:903:2f45:b0:27e:f1d1:74e0 with SMTP id d9443c01a7336-290272b2bd5mr92577745ad.17.1760007491218; Thu, 09 Oct 2025 03:58:11 -0700 (PDT) Received: from localhost ([45.142.165.62]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-b6099f7ab4fsm20659266a12.44.2025.10.09.03.58.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Oct 2025 03:58:10 -0700 (PDT) From: Jinchao Wang To: Andrew Morton , Masami Hiramatsu , Peter Zijlstra , Mike Rapoport , Alexander Potapenko , Randy Dunlap , Marco Elver , Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , "Liang, Kan" , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , Kees Cook , Alice Ryhl , Sami Tolvanen , Miguel Ojeda , Masahiro Yamada , Rong Xu , Naveen N Rao , David Kaplan , Andrii Nakryiko , Jinjie Ruan , Nam Cao , workflows@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-mm@kvack.org, llvm@lists.linux.dev, Andrey Ryabinin , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , kasan-dev@googlegroups.com, "David S. Miller" , Mathieu Desnoyers , linux-trace-kernel@vger.kernel.org Cc: Jinchao Wang Subject: [PATCH v7 16/23] mm/ksw: add self-debug helpers Date: Thu, 9 Oct 2025 18:55:52 +0800 Message-ID: <20251009105650.168917-17-wangjinchao600@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20251009105650.168917-1-wangjinchao600@gmail.com> References: <20251009105650.168917-1-wangjinchao600@gmail.com> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 --- mm/kstackwatch/kstackwatch.h | 2 ++ mm/kstackwatch/watch.c | 34 ++++++++++++++++++++++++++++++++++ 2 files changed, 36 insertions(+) diff --git a/mm/kstackwatch/kstackwatch.h b/mm/kstackwatch/kstackwatch.h index 4045890e5652..528001534047 100644 --- a/mm/kstackwatch/kstackwatch.h +++ b/mm/kstackwatch/kstackwatch.h @@ -52,5 +52,7 @@ 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 f32b1e46168c..9837d6873d92 100644 --- a/mm/kstackwatch/watch.c +++ b/mm/kstackwatch/watch.c @@ -269,3 +269,37 @@ 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