From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 CA8B726AF5 for ; Sun, 21 Jan 2024 04:46:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705812378; cv=none; b=D8l2O0ZlkQUTRLfCGM3CwIcjuvyXH1aMNe2TgikyEWN3HnB8PRCd5D3JSMznsGlfCkKEDUBR0mUhw68mg7ACo9mR3v9YP7GK961fkLCg+Wd/QhKamn4CgE3HW2M/q3ag7GcMLBezh0uj3oUL3tbY739C0yQeE5u7ohwHDsv30jE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705812378; c=relaxed/simple; bh=ik35T/x5yL4zn6sAO0sKXnsdeSg2LD9SzPHvJ/0RNT8=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=mOHDN/7ZAHuqrXOeiWUKqJV3Cn9Xiu7JJTo4Dcj2f9i7HaqXavMwIi0ZjO3LeysRMPb6EyuqS8h2FAhkl2x659bAwp+n1oanHFCgpjLcsJi/L34Q/JR3TuRAi4Q/aeuIdWQSvbiSLql/ST1v9Iag5EMRkXU5pAuXRrv1oh9FSxw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=SlIpCznQ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="SlIpCznQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F55EC433C7; Sun, 21 Jan 2024 04:45:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1705812378; bh=ik35T/x5yL4zn6sAO0sKXnsdeSg2LD9SzPHvJ/0RNT8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=SlIpCznQNRWUWlmcXdGCIovSY8+l5SbuHVyLXRHORtd6cgidKRGjb8pNEFSGGmY0x vtp9ZHkjW0EdOoFrMKmuQTYdFqbdYUiIQBnh/E7kaH5BGIMEE+2akIMSMwdL/sFvAh rTRhPr+wZP2NFO+4GEqQSW7fCgpGuJ+AcmHHiiIo= Date: Sat, 20 Jan 2024 20:45:52 -0800 From: Andrew Morton To: Dylan Hatch Cc: Oleg Nesterov , Kees Cook , Frederic Weisbecker , "Joel Fernandes (Google)" , Ard Biesheuvel , "Matthew Wilcox (Oracle)" , Thomas Gleixner , Sebastian Andrzej Siewior , "Eric W. Biederman" , Vincent Whitchurch , Dmitry Vyukov , Luis Chamberlain , Mike Christie , David Hildenbrand , Catalin Marinas , Stefan Roesch , Joey Gouly , Josh Triplett , Helge Deller , Ondrej Mosnacek , Florent Revest , Miguel Ojeda , linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] getrusage: use sig->stats_lock Message-Id: <20240120204552.c0708fd10fc8e2442c447049@linux-foundation.org> In-Reply-To: References: <20240117192534.1327608-1-dylanbhatch@google.com> <20240119141501.GA23739@redhat.com> <20240119141529.GB23739@redhat.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) 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=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 19 Jan 2024 19:27:49 -0800 Dylan Hatch wrote: > > I applied these to a 5.10 kernel, and my repro (calling getrusage(RUSAGE_SELF) > from 200K threads) is no longer triggering a hard lockup. Thanks, but... The changelogs don't actually describe any hard lockup. [1/2] does mention "the deadlock" but that's all the info we have. So could we please have a suitable description of the bug which these are addressing? And a Reported-by:, a Closes: and a Fixes would be great too.