From nobody Mon Feb 9 15:32:33 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 408B3EDB for ; Sun, 4 Aug 2024 00:51:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722732710; cv=none; b=pkrR/dVjKble229PaEtqpi5fhhwgKOF3LioJaZ7QooG3/0QAHjdbyl+S/bEKnvcvmzzxS0QFPkNrOQm1T2HspRsTJDA102/lb8UcH4ESFy/dadDJE7vXq+sEd/DGm0twBWoKQNvI+bqS/v/XQgWRDYW4SKseZ/qQou7oEv2EiXU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722732710; c=relaxed/simple; bh=UQEDErLI4jcCnZVu0rwmOPRYJ2gt07XxfjlThqg5euI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=QEdRA7XLBHQapZdGDC3oEYoNeKtutPy38z5F7vi1bu90sXAgoc9AZwFUqakEXsI9AGt1ioI741yHe5Y3+QEhmlJqZE68PAzrrIETJMHDm80CpdvPqQ2HYrfFD6rU0C0YUoUip6J0OW6YymAz6dJr8oFTtfi56nCVgYSRZYpW4MI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=EO3EMh9Y; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=A3O34kiQ; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="EO3EMh9Y"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="A3O34kiQ" From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1722732702; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ayf4o19E2VctcrSLOsJe8upAlNvXm11HIiyOTvRvMPY=; b=EO3EMh9Y1vpWMEeVBSKR2VNzkTLDLp0wgRoQyQ8fLhC2JgG3pw/6nkAwuApzT95e8Da4RL PZGPcQAQa5Wc227NyqY05gOgEwH3PBC9jY51r8phR+Yv6HTleP/34mzwgpYD7AcY3SC4ma FaDRLITxUnotQwH+zxFCFYThOIFrXlAnVIKlNxK/4xYaTnBYeuRpSAeq2p5qcGrccUQDzJ s2MoT2wjsPAXr6+C7tmvYEojdlwjoVPVp0x+lml9wxNTr4sR0Wj+189zCxOshrNxuSRU53 EYHxhzw6uQi2m6vGZaj+mTtkWJdRrBf5aU5cO1x+gt66Ovn88yRz8nQp+h6pjg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1722732702; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ayf4o19E2VctcrSLOsJe8upAlNvXm11HIiyOTvRvMPY=; b=A3O34kiQr+VCGjDVHap+so5q9joWvJLcMNlg5Z8JYlxUODEOfTkUht18GdEBl7C1rDpB4z Pze3XAHFLvRYSDAA== To: Petr Mladek Cc: Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , linux-kernel@vger.kernel.org, Sebastian Andrzej Siewior Subject: [PATCH printk v7 04/35] printk: Check printk_deferred_enter()/_exit() usage Date: Sun, 4 Aug 2024 02:57:07 +0206 Message-Id: <20240804005138.3722656-5-john.ogness@linutronix.de> In-Reply-To: <20240804005138.3722656-1-john.ogness@linutronix.de> References: <20240804005138.3722656-1-john.ogness@linutronix.de> 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" From: Sebastian Andrzej Siewior Add validation that printk_deferred_enter()/_exit() are called in non-migration contexts. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: John Ogness Reviewed-by: Petr Mladek --- include/linux/printk.h | 9 +++++---- kernel/printk/internal.h | 3 +++ kernel/printk/printk_safe.c | 12 ++++++++++++ 3 files changed, 20 insertions(+), 4 deletions(-) diff --git a/include/linux/printk.h b/include/linux/printk.h index b937cefcb31c..eee8e97da681 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -161,15 +161,16 @@ int _printk(const char *fmt, ...); */ __printf(1, 2) __cold int _printk_deferred(const char *fmt, ...); =20 -extern void __printk_safe_enter(void); -extern void __printk_safe_exit(void); +extern void __printk_deferred_enter(void); +extern void __printk_deferred_exit(void); + /* * The printk_deferred_enter/exit macros are available only as a hack for * some code paths that need to defer all printk console printing. Interru= pts * must be disabled for the deferred duration. */ -#define printk_deferred_enter __printk_safe_enter -#define printk_deferred_exit __printk_safe_exit +#define printk_deferred_enter() __printk_deferred_enter() +#define printk_deferred_exit() __printk_deferred_exit() =20 /* * Please don't use printk_ratelimit(), because it shares ratelimiting sta= te diff --git a/kernel/printk/internal.h b/kernel/printk/internal.h index 398ecb40d279..dc8bc0890fd2 100644 --- a/kernel/printk/internal.h +++ b/kernel/printk/internal.h @@ -53,6 +53,9 @@ int vprintk_store(int facility, int level, __printf(1, 0) int vprintk_default(const char *fmt, va_list args); __printf(1, 0) int vprintk_deferred(const char *fmt, va_list args); =20 +void __printk_safe_enter(void); +void __printk_safe_exit(void); + bool printk_percpu_data_ready(void); =20 #define printk_safe_enter_irqsave(flags) \ diff --git a/kernel/printk/printk_safe.c b/kernel/printk/printk_safe.c index 6d10927a07d8..4421ccac3113 100644 --- a/kernel/printk/printk_safe.c +++ b/kernel/printk/printk_safe.c @@ -26,6 +26,18 @@ void __printk_safe_exit(void) this_cpu_dec(printk_context); } =20 +void __printk_deferred_enter(void) +{ + cant_migrate(); + __printk_safe_enter(); +} + +void __printk_deferred_exit(void) +{ + cant_migrate(); + __printk_safe_exit(); +} + asmlinkage int vprintk(const char *fmt, va_list args) { #ifdef CONFIG_KGDB_KDB --=20 2.39.2