From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 5479D4A8A1F for ; Fri, 11 Sep 2026 17:58:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789149501; cv=none; b=qY0W6KKEposmq/NQyopVjVfPz3/BZ/i2zNCFZHOCLqKjsVyQ2SVoswiTWFad4ScA0i7wQ3WOcshxl+75gsasLJwnTGNHkbeyk3sbRA4h7qx22Aci9pggdUBagjyJg7u9r6zDK61mL/JoWWslFXePyaziD2/8+mHAA3yVieUzRxU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789149501; c=relaxed/simple; bh=F5RjB8TbgTnQG7w34f1Vg4WbZ21FH7vz2UBoLvxn/SM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=a34xFhX/hjgWXzSw08GXraeThmb+w7FjXqquZ4y7ltZE4Pgmns8dnzwkyTobSL7CYNVmcaHgVBtQrhC/kk1N2UQlxhNtN8bJ83xx5JoahVB3Gx46DSrKetsimFJD4Sz5CHXvW2TXL6Qn6mfzftdGF9ckAPON8Saf70T5M2d+U+s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BvagNmnN; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BvagNmnN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D4111F00893; Fri, 11 Sep 2026 17:58:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789149498; bh=NSJDN7ZPGzLiv66xz7l0vvlTn1DgWKJRBA31R46kPR4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BvagNmnNHpCyrXPykGYPAE0c+y4VsHuRpyUFY/EBXezk1BoVnkvab8VfWjV8PuCe/ 7ix7E9gxZ73cUfAD+QIKVSxqk0T3nkeWPj/qlj4fa/5bYoFiSY/20vBn1N9sg4KlDB W5h7yUTlbM3aj0wWFSJQqJPXDyzTNi8s59fuVTVQLSqZt78FaH0orHZP+s7AFoBWxW AYEwLAScuBjFo9Jd6rIfwRFC6pT8hBiz+abhzfOPbUpHnLkmTnW63jKoex4JrEtdX/ CpWenCEVQtVg3FGCLvSavwvkv+RdbGGyXq3DiOiagEvgURwzKyR/XUZT8YxMbeEmH1 9gukM8h7APYdA== From: Sasha Levin To: stable@vger.kernel.org Cc: Nilesh Javali , Sashiko , "Martin K. Petersen (Oracle)" , Sasha Levin Subject: [PATCH 6.12.y] scsi: qla2xxx: Fix soft lockup polling continuation IOCB signature Date: Fri, 11 Sep 2026 13:58:16 -0400 Message-ID: <20260911175816.1283053-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026090956-molasses-octopus-b86b@gregkh> References: <2026090956-molasses-octopus-b86b@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Nilesh Javali [ Upstream commit d7e3fa7d06bf7fcaac186d3c4d635caac166d36c ] qla27xx_copy_multiple_pkt() and qla27xx_copy_fpin_pkt() poll rsp_q->ring_ptr->signature for RESPONSE_PROCESSED (0xDEADDEAD) to decide whether the next continuation IOCB has arrived, spinning on cpu_relax() without advancing the ring or decrementing the entry count while it has not. response_t::signature lives at byte offset 60, but a continuation IOCB (sts_cont_entry_t / struct sts_cont_entry_ext) carries raw FC frame payload at that offset (data[56..59]). A received frame whose payload bytes happen to equal 0xDEADDEAD is therefore misread as "not yet arrived", and the loop spins forever in interrupt/DPC context, causing a CPU soft lockup. The poll is also unnecessary: callers of qla27xx_copy_multiple_pkt() (PT_LS4_UNSOL and the NVMe purls path) already gate on qla_chk_cont_iocb_avail(), which guarantees all entry_count IOCBs are present before copying begins. The sibling helper __qla_copy_purex_to_buffer() already drops the signature poll and relies on the entry_type == STATUS_CONT_TYPE guard instead. Remove the signature busy-wait from both helpers, keeping the entry_type guard, and gate the FPIN path with qla_chk_cont_iocb_avail() so it defers and re-processes on the next interrupt once all continuation IOCBs have arrived, mirroring the ELS_AUTH_ELS and PT_LS4_UNSOL arms. With this the signature field is never read on a continuation IOCB, eliminating the payload-aliasing lockup. Fixes: 9f2475fe7406 ("scsi: qla2xxx: SAN congestion management implementation") Cc: stable@vger.kernel.org Reported-by: Sashiko Signed-off-by: Nilesh Javali Link: https://patch.msgid.link/20260730155838.2119230-15-njavali@marvell.com Signed-off-by: Martin K. Petersen (Oracle) [ replaced unavailable qla_rsp_ring_rewind_to() with direct ring pointer and index assignments ] Signed-off-by: Sasha Levin --- drivers/scsi/qla2xxx/qla_isr.c | 33 ++++++++++++++++----------------- 1 file changed, 16 insertions(+), 17 deletions(-) diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c index 07b08119af0b0..f2f68eb2bde99 100644 --- a/drivers/scsi/qla2xxx/qla_isr.c +++ b/drivers/scsi/qla2xxx/qla_isr.c @@ -910,14 +910,6 @@ qla27xx_copy_multiple_pkt(struct scsi_qla_host *vha, void **pkt, do { while ((total_bytes > 0) && (entry_count_remaining > 0)) { - if (rsp_q->ring_ptr->signature == RESPONSE_PROCESSED) { - ql_dbg(ql_dbg_async, vha, 0x5084, - "Ran out of IOCBs, partial data 0x%x\n", - buffer_copy_offset); - cpu_relax(); - continue; - } - new_pkt = (sts_cont_entry_t *)rsp_q->ring_ptr; *pkt = new_pkt; @@ -1194,14 +1186,6 @@ qla27xx_copy_fpin_pkt(struct scsi_qla_host *vha, void **pkt, do { while ((total_bytes > 0) && (entry_count_remaining > 0)) { - if (rsp_q->ring_ptr->signature == RESPONSE_PROCESSED) { - ql_dbg(ql_dbg_async, vha, 0x5084, - "Ran out of IOCBs, partial data 0x%x\n", - buffer_copy_offset); - cpu_relax(); - continue; - } - new_pkt = (sts_cont_entry_t *)rsp_q->ring_ptr; *pkt = new_pkt; @@ -4109,9 +4093,24 @@ void qla24xx_process_response_queue(struct scsi_qla_host *vha, "SCM not active for this port\n"); break; } + if (qla_chk_cont_iocb_avail(vha, rsp, + (response_t *)pkt, rsp_in)) { + /* + * ring_ptr and ring_index were + * pre-incremented above. Reset them + * back to current. Wait for next + * interrupt with all IOCBs to arrive + * and re-process. + */ + rsp->ring_ptr = (response_t *)pkt; + rsp->ring_index = cur_ring_index; + + ql_dbg(ql_dbg_init, vha, 0x5095, + "Defer processing FPIN...\n"); + return; + } pure_item = qla27xx_copy_fpin_pkt(vha, (void **)&pkt, &rsp); - __update_rsp_in(is_shadow_hba, rsp, rsp_in); if (!pure_item) break; qla24xx_queue_purex_item(vha, pure_item, -- 2.53.0