From nobody Thu Oct 2 02:15:07 2025 Received: from mail-pg1-f177.google.com (mail-pg1-f177.google.com [209.85.215.177]) (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 96F8A2FFDDE for ; Wed, 24 Sep 2025 12:00:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.177 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758715219; cv=none; b=jpr/lVpNWhm+ADAxTyC/VH/h9T3TwrUc30nYFSpNomyhzgh1k5VwUx+o4CsAKH9CMTjzLansq5IRUsKeqDhq4j/WDA5YZk9BG+Q0AUaWhCD7fL8wm5JMvOhGf3M9Suc8xspkg2ylZQDbhi721kl2CEDt0R8RBEhG/Lxk5DonDYk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758715219; c=relaxed/simple; bh=zgbvGJBSx4YBKNkqO/qzz/La9XfnZ3vAatfFaQMoL7I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=tmtL3CcyZhcALgCoZrhu0jm7ThTaTMLfykimWuihnviTWowMrqV9S33y231I/xnYQNK/xMlewc4gfj/AYYD5HDQs6SmA3MIXQB8XKa2D+y+x7U6p8g7zJAnCKpr3Tyj95lE+x3CQhFxRQgTGJz/WQAtH3Nz6fSwO/8BHLJhoxqA= 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=fW0ETLeQ; arc=none smtp.client-ip=209.85.215.177 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="fW0ETLeQ" Received: by mail-pg1-f177.google.com with SMTP id 41be03b00d2f7-b5241e51764so5251791a12.1 for ; Wed, 24 Sep 2025 05:00:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1758715215; x=1759320015; darn=vger.kernel.org; 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=fW0ETLeQCFX8OFWb9u250UoVfhDWanBM+gtDWVOLh0/w6XBqCDew2W0/fZkeJNJiZ1 qMORdyFC2XLNKCYNu4P08Y3EanKlp0FmAiHO0HMpwTd7b/DEMCez4DK/ABIXfF/P81mZ np1yGnCd4gD37MIK/3v2bFzRIJz5oKLP5Y4PaxKtE5ctLPwRVByKYVJq53tCe8tb2ffL oyYfuzw7BkjT1g4t8DfbYfn2/AJyt1Rwl3ls6piKNdQSaRnZ6gKunmEeh2bohr8NZOkH b+sESF4Zql4iaDXIVvlXDxsrmaWTvU2jgUQ5MQqJQod0P9Hpapj/VJbBWnQzlveryClN 43ng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758715215; x=1759320015; 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=OEltuCT0pnkcVdJEvMOYdU4LUaYydDRwyp93QjGR5dIZghQ4yYU5VCkaUtlHe1PSH3 /k45Xep08EJXC6ZX4smTcoYuUqRU13uDcjBBPBf5mS59Tc5VMIRqaE5ZrjY5p57WE1zN RFejW16fW3aWM9xEhLXRZKJ/CJRvcGRugJZH4eLDLM07rk/4Q4IqHA/CaX29iKm8Y1FY ixaZ8woaawyKnRj0QRyalqI9YP/NHy39+og8vEq9gYaRTpS3VZmVdlsa1hKWgjR8aHpc bm1GvQTLHWPkOYfD9XkcNk5aCaX1wsjWZeIfI856KQwuSvOxDQWD9Wp6vOvYRaTL5rzJ e9CQ== X-Forwarded-Encrypted: i=1; AJvYcCUcxaBWtL7EgvOTsp64jQnUIxQP5bHCYpCiH9Em9kEbISEcBd0MYPHT8ijdfukoroNaxBgXeYnhOFS2YEE=@vger.kernel.org X-Gm-Message-State: AOJu0YxQ0ud7ioMseKAh1PRlL0C6UkFyghJZQtDyC09fvEArmAw2+95T K1IyDK/lDGFRnIhvkeENrlZkyLUP/ovL4sLxiJanAr5iOp63c/wN5Cfd X-Gm-Gg: ASbGncvTB40NTGWOyL+SJ/puTxHUsmX9MezNj/r925OZCMZ2rBrpIhqAYwcPZGGMvUx SagvAoPhqtOXHCFsr/WgyhDp8oPsuzgsjV/7rl/y5FXyEwAjGkiqCPsB5GPTPrdeOevu+0R/L5c qlwAgATrt1YwEHE/6VW11JsJHgCxNJvv6L3TpL/7hHdUJf3Qi2H2SE1osfUagEkwqGhbQ/FCp0+ xkwjGBXUXu4M/c9Ve3v4rBwbsu0RgyRCwcgq0NY1fdFv6N5c4Xb1mv3sN7POh1TdIAmme2qn6UY ISebzg+HCVL0kudczahrnM3wh0Ooq9798ImpeUYP4tE9ZRTM9iWY99IHbOhScv21wW59dpmjAwV HRDEW4DHLARFLOQvJtSppqo4= X-Google-Smtp-Source: AGHT+IG5AidgxW/pjwMRKvZXF7BqnVmuGXBXEakixJFL1V8tNMywu8qGgSCIq0aUezqYi7cmWgbNjA== X-Received: by 2002:a17:903:2450:b0:268:f83a:835a with SMTP id d9443c01a7336-27cc9a91248mr60312585ad.60.1758715214591; Wed, 24 Sep 2025 05:00:14 -0700 (PDT) Received: from localhost ([103.88.46.62]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-269802de5dbsm189402185ad.84.2025.09.24.05.00.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Sep 2025 05:00:13 -0700 (PDT) From: Jinchao Wang To: Andrew Morton , Masami Hiramatsu , Peter Zijlstra , Mike Rapoport , Alexander Potapenko , Randy Dunlap , 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 v5 16/23] mm/ksw: add self-debug helpers Date: Wed, 24 Sep 2025 19:59:22 +0800 Message-ID: <20250924115931.197077-1-wangjinchao600@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250924115124.194940-1-wangjinchao600@gmail.com> References: <20250924115124.194940-1-wangjinchao600@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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_le= n); int ksw_watch_off(struct ksw_watchpoint *wp); +void ksw_watch_show(void); +void ksw_watch_fire(void); =20 #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 =3D 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 =3D current->ksw_ctx.wp; + + if (!wp) { + pr_info("nothing to fire\n"); + return; + } + + ptr =3D (char *)wp->attr.bp_addr; + pr_warn("watch triggered immediately\n"); + *ptr =3D 0x42; // This should trigger immediately for any bp_len +} +EXPORT_SYMBOL_GPL(ksw_watch_fire); --=20 2.43.0