From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 8B80628AB07; Thu, 8 May 2025 19:46:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746733576; cv=none; b=uH6pnNx03Civ/PJi01TwT0cp3ehRehXtAr28I0j8UQRFpAiZUCMfCS7fnskaGQiIxA8HPL7G8PSbECTgqla6EFpkPZVaIGFWYhTf5xEF8zV+6zA6EOlWKiSX83y0cLJU17FVuy+wkZpcNGTM4b3muZyqaZpuNqv4PHDK1GF4E4Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746733576; c=relaxed/simple; bh=yyvI7DAXm3rfJ/sbUu5kfKFg14e8FmbkKV8nRA5xZF8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QBxeJnfIWxhKW3z6sEw8xRArrkt9UhREMKgXeXT66FrZt+46BeMZP8DvmOQEuWcw2EWb9KRL4yXVUEF11tczMntSo7IjjXZtWKvsC1qVnew3sHJelG3CDP7EkeXq2D+2IwdFIR+v7blc0Knz6eUPuIclWCM+LRBbIKA4rURK6aw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=oQ0kbt66; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="oQ0kbt66" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=OHiKRzCBkFciXiXYaG9F67Fcg4ghNHssFOoXfh5Nyc8=; b=oQ0kbt66eLjKZjqvg8p1lYvnvG RjUVIgTkUC6VFWI6qheNEBc7wP1pRnpHKpxUMbZsaB9EkHngCeZ0QSMVrJkUubPF55OWXWT1BoFOq 15gAS8pDzNWq4uASqW3vIjLf6NDSDGRUUYDFTRqo1IMGFOveGHJR2xw6cb4pc5jZwIJIwjAVWwwAN VbqDEn1Q/2DiM3POX2BDwYiysfUvtU96xaBTqxMSGzGYEs7Pv3QqHxudRfBSaqLg0PNw5BYfF/H0f c34fzJZz2zpJlGDeW8HiMjJYeAcV/PywtkZw0UCQEWJD5T5Wh08Yx9mYH+a0fr0gpQsGq09c9TouT g39YXy2w==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1uD7C3-00000002pgX-0uXY; Thu, 08 May 2025 19:46:06 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id BF12930005A; Thu, 8 May 2025 21:46:05 +0200 (CEST) Date: Thu, 8 May 2025 21:46:05 +0200 From: Peter Zijlstra To: Frederic Weisbecker Cc: linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org, x86@kernel.org Subject: Re: [tip: perf/core] perf: Fix irq work dereferencing garbage Message-ID: <20250508194605.GA8552@noisy.programming.kicks-ass.net> References: <174670046919.406.15885032121099672652.tip-bot2@tip-bot2> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Thu, May 08, 2025 at 09:11:23PM +0200, Frederic Weisbecker wrote: > Le Thu, May 08, 2025 at 10:34:29AM -0000, tip-bot2 for Frederic Weisbecker a écrit : > > The following commit has been merged into the perf/core branch of tip: > > > > Commit-ID: 88d51e795539acd08bce028eff3aa78748b847a8 > > Gitweb: https://git.kernel.org/tip/88d51e795539acd08bce028eff3aa78748b847a8 > > Author: Frederic Weisbecker > > AuthorDate: Mon, 28 Apr 2025 13:11:47 +02:00 > > Committer: Peter Zijlstra > > CommitterDate: Fri, 02 May 2025 12:40:40 +02:00 > > > > perf: Fix irq work dereferencing garbage > > > > The following commit: > > > > da916e96e2de ("perf: Make perf_pmu_unregister() useable") > > > > has introduced two significant event's parent lifecycle changes: > > > > 1) An event that has exited now has EVENT_TOMBSTONE as a parent. > > This can result in a situation where the delayed wakeup irq_work can > > accidentally dereference EVENT_TOMBSTONE on: > > > > CPU 0 CPU 1 > > This is missing the most important (and boring) part of the changelog :-) > > > Signed-off-by: Peter Zijlstra (Intel) > > And I suspect some automatic check will also yell at some point at missing Sob. Doh, script fail :/ Let me go fix.