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 B8FE72F12AC for ; Fri, 11 Sep 2026 17:52:27 +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=1789149148; cv=none; b=d/neY7cP2mGiv18tqo10ciAzIgInzQdT7Wusuqk+S2156r9WKoiQtmjnV5zn8Cdhnbt4KAEx9D+qOOcoCpW7GjQtsEQ+9FVYZkawNJsfmkyI4Juxrx1qYSQqClyt3TrZcsSwX5zVyjcSAOcvqGilnknx/Hv5yffcQ4QpirrBb/0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789149148; c=relaxed/simple; bh=wdvZMAt/IO4nuA5nD+4XctcB9zo2An1r+M1cvOC57W4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sQaokN2e2Cw+OFSDI1gNW97p2Flpcq1TQzQqh+m13KkA6YdX+3Hr5uAk6wqUGUq3lTEf+BZI956qj5S7SCLtqQJALBnJJDBXuA2mY+bBC+hSKNGYnIdMIKIJyDHx0G11PPogAn7GVuMapBSCnh/sv9kQ2Ds66UuAOj/j2GrCpwg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AGkxYrJz; 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="AGkxYrJz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E97901F000FF; Fri, 11 Sep 2026 17:52:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789149147; bh=DRcfKUsb3AQb5PEKiVMvptBrQsMdgMfU5sTb3t83y4g=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=AGkxYrJznqx6H3ciwwSOrXmM7trT9K037o3kho/BXpG/5ebkqOsBondVV3YQ2rdNW pmSzxdca5jfzT7ujwhcH1tB9/3sW+igQLJXCfbrA45jtuLP5M5JkL/sWGd7jjixq7v f/7e1is52S7Nl3FomiFYffJ+T6nxsrc9WzvfqpxdPJA1Tnn0xpGGdAmM3G4qbA598H 9X1JFHVDQDKK5IymX8znO3hROM7M0NhTxvr8A7S9VVK+BgvdQpQEvoRvpzHoHorgpF XGRY62SyACqYVsxnv9A29v8w7v1++76h0Qci2ML8uE5deeE7EOWo4FfP8Er9Ph0reM QO896+WcZTvvg== From: Sasha Levin To: stable@vger.kernel.org Cc: Nilesh Javali , Sashiko , "Martin K. Petersen (Oracle)" , Sasha Levin Subject: [PATCH 6.18.y] scsi: qla2xxx: Fix soft lockup polling continuation IOCB signature Date: Fri, 11 Sep 2026 13:52:25 -0400 Message-ID: <20260911175225.1277230-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026090955-retaining-dynamic-f026@gregkh> References: <2026090955-retaining-dynamic-f026@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 bf301408985bf..50c14c25a38ba 100644 --- a/drivers/scsi/qla2xxx/qla_isr.c +++ b/drivers/scsi/qla2xxx/qla_isr.c @@ -921,14 +921,6 @@ 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; @@ -1205,14 +1197,6 @@ 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; @@ -4142,9 +4126,24 @@ 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