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{ "id": 2235186, "url": "http://patchwork.ozlabs.org/api/1.2/covers/2235186/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-ide/cover/20260508195051.188207-4-cassel@kernel.org/", "project": { "id": 13, "url": "http://patchwork.ozlabs.org/api/1.2/projects/13/?format=api", "name": "Linux IDE development", "link_name": "linux-ide", "list_id": "linux-ide.vger.kernel.org", "list_email": "linux-ide@vger.kernel.org", "web_url": null, "scm_url": null, "webscm_url": null, "list_archive_url": "", "list_archive_url_format": "", "commit_url_format": "" }, "msgid": "<20260508195051.188207-4-cassel@kernel.org>", "list_archive_url": null, "date": "2026-05-08T19:50:51", "name": "[v3,0/2] ata: fix deferred QC handling for port multipliers", "submitter": { "id": 87751, "url": "http://patchwork.ozlabs.org/api/1.2/people/87751/?format=api", "name": "Niklas Cassel", "email": "cassel@kernel.org" }, "mbox": "http://patchwork.ozlabs.org/project/linux-ide/cover/20260508195051.188207-4-cassel@kernel.org/mbox/", "series": [ { "id": 503439, "url": "http://patchwork.ozlabs.org/api/1.2/series/503439/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-ide/list/?series=503439", "date": "2026-05-08T19:50:51", "name": "ata: fix deferred QC handling for port multipliers", "version": 3, "mbox": "http://patchwork.ozlabs.org/series/503439/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2235186/comments/", "headers": { "Return-Path": "\n <linux-ide+bounces-5700-incoming=patchwork.ozlabs.org@vger.kernel.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linux-ide@vger.kernel.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=TxYfdv3B;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=172.234.253.10; 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Fri, 8 May 2026 19:51:10 +0000 (UTC)", "by smtp.kernel.org (Postfix) with ESMTPSA id 88AFDC2BCB0;\n\tFri, 8 May 2026 19:51:08 +0000 (UTC)" ], "ARC-Seal": "i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1778269870; cv=none;\n b=GNMIeeN5zYgPJ2OZWS9g3e42ZsFmy2Sg36i06dNc/Zrbnz/rqV8ieZU/PK73fBYUvmV5ZUAg2554/mqQmcdKi6EWnTtUvqNnnNP2Ku3MvCL84puO3IK7kkCkj2aIKx8lzwNbsXHECOTfbjZCdNZdR232q1+cznUxM85xYX/SxSo=", "ARC-Message-Signature": "i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1778269870; c=relaxed/simple;\n\tbh=rYsTj0M1yvVHhMG8UlQsWNxYUfAz08kCQBbBRkaHjfg=;\n\th=From:To:Cc:Subject:Date:Message-ID:MIME-Version;\n b=MaYCI85Jbl11ywY4/6EXmtxrfnyv9Rx7L58qEu7CSIIb2JCkyULSgR3Tk7bT9l+d12Jr2dfWoo4dg4r8LftpxEG/WJ9eHp3LgaGc7TjjSxvwAewBGRWVTW9MSUWneTH0/SYKHQMLN6UxMXbVGEoenycMs788bnNgQRO7RpPGgMc=", "ARC-Authentication-Results": "i=1; smtp.subspace.kernel.org;\n dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org\n header.b=TxYfdv3B; arc=none smtp.client-ip=10.30.226.201", "DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org;\n\ts=k20201202; t=1778269870;\n\tbh=rYsTj0M1yvVHhMG8UlQsWNxYUfAz08kCQBbBRkaHjfg=;\n\th=From:To:Cc:Subject:Date:From;\n\tb=TxYfdv3BIwqC52E/B5q1Z3FGds0JeGDdZSdVvPvwBpC9Vu57eIXg679LbvqhrXiAj\n\t Vq9GRJg2taSt0vYA+7xgpj/V0pKvfQaywN5IITFzf91tOGrW+HC4YP3U2amlLxjIOt\n\t IiZby+yIirCZXD2OkVOFmZEPUdR9blYbvCuSaSLUfRtNc6bV2Rz2vTqj2zl6PJ/6Ul\n\t HqEbpjdSnuQgfGEEuVGyCBlsDXLekej+ddjkijgNu/On7r38GYyC24Bk0DVuqtoLKd\n\t XyEaOSXG/fNSZ8WY23TJjXOZwsbiSSVIGqGdCwjH3d4OG17EFlH+MgYLTZNCMF1ZBr\n\t dyzc79rCKzqfw==", "From": "Niklas Cassel <cassel@kernel.org>", "To": "Tommy Kelly <linux@tkel.ly>,\n\tDamien Le Moal <dlemoal@kernel.org>,\n\tNiklas Cassel <cassel@kernel.org>,\n\tJohn Garry <john.g.garry@oracle.com>,\n\t\"Martin K. Petersen\" <martin.petersen@oracle.com>", "Cc": "linux-ide@vger.kernel.org", "Subject": "[PATCH v3 0/2] ata: fix deferred QC handling for port multipliers", "Date": "Fri, 8 May 2026 21:50:51 +0200", "Message-ID": "<20260508195051.188207-4-cassel@kernel.org>", "X-Mailer": "git-send-email 2.54.0", "Precedence": "bulk", "X-Mailing-List": "linux-ide@vger.kernel.org", "List-Id": "<linux-ide.vger.kernel.org>", "List-Subscribe": "<mailto:linux-ide+subscribe@vger.kernel.org>", "List-Unsubscribe": "<mailto:linux-ide+unsubscribe@vger.kernel.org>", "MIME-Version": "1.0", "X-Developer-Signature": "v=1; a=openpgp-sha256; l=1492; i=cassel@kernel.org;\n h=from:subject; bh=rYsTj0M1yvVHhMG8UlQsWNxYUfAz08kCQBbBRkaHjfg=;\n b=owGbwMvMwCV2MsVw8cxjvkWMp9WSGDL/2c1e2V9QrMYdu+LPj6I4rd4m3xNdz5MFdL48PnTrw\n sbtW3zud5SyMIhxMciKKbL4/nDZX9ztPuW44h0bmDmsTCBDGLg4BWAiumcZ/kpunhR7s9nq4Ckl\n LZWkvGnWZ+7MudG5+86ZHaEH7Zg2LZVhZLicxhN+7Emybfvf5pl7WloVuU0EzKxnXcl6Xbj40PS\n ApewA", "X-Developer-Key": "i=cassel@kernel.org; a=openpgp;\n fpr=5ADE635C0E631CBBD5BE065A352FE6582ED9B5DA", "Content-Transfer-Encoding": "8bit" }, "content": "Hello all,\n\nTommy Kelly reported a regression with PMP that use CBS:\nhttps://lore.kernel.org/linux-ide/ce09cc21-a8e9-4845-b205-35411e22fba9@tkel.ly/\n\nIt turns out that the ap->excl_link logic used for PMP that use CBS is\nincompatible with the deferred qc issuing via a workqueue.\nThis is fixed in patch 1/2.\n\nWhile looking at the code, it turns out that the deferred qc issuing via\nworkqueue is misdesigned. It assumed that we can't mix NCQ and non-NCQ\ncommands on the same port. The limitation is that you can not mix NCQ and\nnon-NCQ commands on the same drive. However, with a PMP with FBS, you can\nissue (mixed NCQ and non-NCQ commands) to the different drives. Thus, move\nthe saved deferred QC from struct ata_port to struct ata_link. This is\nfixed in patch 2/2.\n\n\nChanges since v1:\n-Avoid a local variable in sata_pmp_qc_defer_cmd_switch(), call\n ata_std_qc_defer(qc) inside the switch() directly instead.\n-Fix a typo, such that the the code actually compiles... Sorry for that.\n\n\nNiklas Cassel (2):\n ata: libata-scsi: do not use the deferred QC feature on PMPs with CBS\n ata: libata-scsi: do not needlessly defer commands when using PMP with\n FBS\n\n drivers/ata/libata-core.c | 16 ++++---\n drivers/ata/libata-eh.c | 8 ++--\n drivers/ata/libata-pmp.c | 26 +++++++++--\n drivers/ata/libata-scsi.c | 95 ++++++++++++++++++++++++---------------\n include/linux/libata.h | 8 ++--\n 5 files changed, 101 insertions(+), 52 deletions(-)" }