From mboxrd@z Thu Jan 1 00:00:00 1970 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 F029C12CDAE for ; Fri, 19 Jul 2024 13:48:23 +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=1721396905; cv=none; b=uDxQ+kP7sqiBY7VVFvfg/vS+Y7qnYBaexrsHI8CbtYb752uWO0mLHpM5vdzk6JWtGZzmn5+DVInpPf2wyg0iBlehe22HLVfTxFaFjW0p0dMyNdtIFdw/eG/oi8Ze/CzExoP7mcIBJfisNRF49/w5eNPMzmHXh8ND/0raaSCOmMs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721396905; c=relaxed/simple; bh=s7ETTH33fA0SIwykyqhyinUWuBUMdhpnAhbmqh0CCd0=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=UkZUaPOvJDxqCNJxoECjiS8j1e7por40JRn2J/VjIl/h0y3Y1gc+9/GWZhaaxUHVBX5A4zKjPzKkpjqOtqnL3/2WdNiJcX8d+yk3Wg6hoZ5z1eGczPXHECA5ZT78ycUkRbxYv/biqH2wxrSKQ/Fp3/IIP+fP2rhbVTrXBFcTkVY= 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=u83d2GBe; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=OinDvsH3; 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="u83d2GBe"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="OinDvsH3" From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1721396899; 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; bh=5++DmDEVMSGdhpk9gWUbi5tzr3w5rBzS5Sh6yl7CFes=; b=u83d2GBe+IlKXI6PXMygfLeqFASMg70MmjSi5TxiiEOw+qa7Piist/PIPZ+yaT+NORk8Eu jKzKTvu/JeFT4cXW1oeTK4ZKcUs+XpZebFZy1lK7fWAS8aahcxoutwa6Nq/u9mIrEkrT/l K9Gx3e0A+Wm3L7rc7i6bWpM6dXdy7JQo/Y1n4qW0UOJarpapJZyD5ophjUGPNY8Hrtg9ky CEXJYUdywJShGrSKOLIcUSGyQvo43zKSywugDmhbp868wqzIe4kl9iNR0XlL99bTPHCxVN h6Kwia14CS+2/pgcb2vXoc/6knnYUVUybiIXSkrkGRCUBvYXnQuvnsgomiNFkA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1721396899; 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; bh=5++DmDEVMSGdhpk9gWUbi5tzr3w5rBzS5Sh6yl7CFes=; b=OinDvsH3+dlZjO771LEl9ROOffkLTYU/6QytqmiReRO8iCTlwmDC2mU/vvMUyCt0RI5zif 0XOrhMTPt6Rbz4Ag== To: Petr Mladek Cc: Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , linux-kernel@vger.kernel.org, Juri Lelli Subject: [PATCH printk 0/1] alternate fix for nbcon_cpu_emergency_flush() Date: Fri, 19 Jul 2024 15:54:17 +0206 Message-Id: <20240719134818.3311665-1-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: 8bit Hi Petr, Currently in linux-next we have commit b955f0eead54 ("printk: nbcon: Fix nbcon_cpu_emergency_flush() when preemptible"). But as you pointed out [0], there is no need to disable preemption at all if we only need to know if the current CPU is in emergency state. Here is an alternative patch that correctly addresses the issue by avoiding the migration checks. Since the previous patch is not yet mainline, perhaps you want to use this one instead in order to avoid a revert. Up to you. John Ogness [0] https://lore.kernel.org/lkml/Zn7b8g1HtuTIAwyi@pathway.suse.cz John Ogness (1): printk: nbcon: do not require migration disabled for nbcon_get_cpu_emergency_nesting() kernel/printk/nbcon.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) base-commit: c51cf7315db1392af58b909d1004133f6dbf0bf6 -- 2.39.2