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[195.250.132.146]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-48af5056a16sm3398058f8f.18.2026.09.29.05.07.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 29 Sep 2026 05:07:52 -0700 (PDT) From: Petr Mladek To: John Ogness Cc: Sergey Senozhatsky , Steven Rostedt , Marcos Paulo de Souza , Chris Down , Naveen Kumar Chaudhary , linux-kernel@vger.kernel.org, Petr Mladek Subject: [PATCH v5 10/16] printk: Allow to debug misuse of add_or_update_preferred_console() Date: Tue, 29 Sep 2026 14:05:40 +0200 Message-ID: <20260929120546.328616-11-pmladek@suse.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260929120546.328616-1-pmladek@suse.com> References: <20260929120546.328616-1-pmladek@suse.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit __add_preferred_console() should always be called only when either @name or @devname is defined. Allow to debug the case when they are misused. Use WARN_ON() because it is rather an implementation problem, it should never happen. Also the consoles are typically added during boot so this should not panic a running system even when panic_on_warn is enabled. Signed-off-by: Petr Mladek --- kernel/printk/printk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index b458a920ce5a..683083405230 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2585,7 +2585,7 @@ static int add_or_update_preferred_console(unsigned int i, pc = &preferred_consoles[i]; - if (!name && !devname) + if (WARN_ON(!name && !devname)) return -EINVAL; if (devname) { -- 2.55.0