From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 17C776A18A for ; Thu, 29 Jul 2021 17:59:04 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 0C281A0F0 for ; Thu, 29 Jul 2021 17:59:04 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id 587EEA0E2 for ; Thu, 29 Jul 2021 17:59:03 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 2F28E42C65 for ; Thu, 29 Jul 2021 17:59:03 +0200 (CEST) Message-ID: <32e03cd7-1a0c-459f-e190-ce76e32d3c98@proxmox.com> Date: Thu, 29 Jul 2021 17:59:01 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.0 Content-Language: en-GB To: Proxmox VE development discussion , Fabian Ebner References: <20210729095031.90694-1-f.ebner@proxmox.com> From: Thomas Lamprecht Cc: =?UTF-8?Q?Fabian_Gr=c3=bcnbichler?= , Wolfgang Bumiller In-Reply-To: <20210729095031.90694-1-f.ebner@proxmox.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL 0.385 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: [pve-devel] applied: Re: [PATCH v2 qemu] io_uring: resubmit when result is -EAGAIN X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 29 Jul 2021 15:59:04 -0000 On 29/07/2021 11:50, Fabian Ebner wrote: > Linux SCSI can throw spurious -EAGAIN in some corner cases in its > completion path, which will end up being the result in the completed > io_uring request. > > Resubmitting such requests should allow block jobs to complete, even > if such spurious errors are encountered. > > Signed-off-by: Fabian Ebner > --- > > Changes from v1: > * make it a patch for pve-qemu instead of the qemu submodule > * use v2 of the patch with a comment by Stefan Hajnoczi > > ...uring-resubmit-when-result-is-EAGAIN.patch | 49 +++++++++++++++++++ > debian/patches/series | 1 + > 2 files changed, 50 insertions(+) > create mode 100644 debian/patches/extra/0002-block-io_uring-resubmit-when-result-is-EAGAIN.patch > > applied, thanks! For others regarding bump: while this is def. correct it actually increases the likelihood of a kernel crash with old (<< pve-kernel-5.11.22-3-pve 5.11.22-6) kernels. As now it was either a crash or a block job error, this patch basically converts the block job errors into crashes on bad old kernel and into avoiding a block job error on the OK behavior of resubmitting on EAGAIN on new kernels. Those that saw neither crash nor block job errors won't notice a difference either way.