All of lore.kernel.org
 help / color / mirror / Atom feed
From: James Smart <jsmart2021@gmail.com>
To: linux-scsi@vger.kernel.org
Cc: James Smart <jsmart2021@gmail.com>,
	Dick Kennedy <dick.kennedy@broadcom.com>
Subject: [PATCH 03/11] lpfc: Fix kernel crash at lpfc_nvme_info_show during remote port bounce
Date: Mon,  4 Nov 2019 16:57:00 -0800	[thread overview]
Message-ID: <20191105005708.7399-4-jsmart2021@gmail.com> (raw)
In-Reply-To: <20191105005708.7399-1-jsmart2021@gmail.com>

When reading sysfs nvme_info file while a remote port leaves and comes
back, a NULL pointer is encountered. The issue is due to ndlp list
corruption as the the nvme_info_show does not use the same lock as the
rest of the code.

Correct by removing the rcu_xxx_lock calls and replace by the host_lock
and phba->hbaLock spinlocks that are used by the rest of the driver.
Given we're called from sysfs, we are safe to use _irq rather than
_irqsave.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
---
 drivers/scsi/lpfc/lpfc_attr.c | 40 ++++++++++++++++++++--------------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c
index 2d090ea2b736..3f30bc02da9e 100644
--- a/drivers/scsi/lpfc/lpfc_attr.c
+++ b/drivers/scsi/lpfc/lpfc_attr.c
@@ -176,7 +176,6 @@ lpfc_nvme_info_show(struct device *dev, struct device_attribute *attr,
 	int i;
 	int len = 0;
 	char tmp[LPFC_MAX_NVME_INFO_TMP_LEN] = {0};
-	unsigned long iflags = 0;
 
 	if (!(vport->cfg_enable_fc4_type & LPFC_ENABLE_NVME)) {
 		len = scnprintf(buf, PAGE_SIZE, "NVME Disabled\n");
@@ -347,7 +346,6 @@ lpfc_nvme_info_show(struct device *dev, struct device_attribute *attr,
 	if (strlcat(buf, "\nNVME Initiator Enabled\n", PAGE_SIZE) >= PAGE_SIZE)
 		goto buffer_done;
 
-	rcu_read_lock();
 	scnprintf(tmp, sizeof(tmp),
 		  "XRI Dist lpfc%d Total %d IO %d ELS %d\n",
 		  phba->brd_no,
@@ -355,7 +353,7 @@ lpfc_nvme_info_show(struct device *dev, struct device_attribute *attr,
 		  phba->sli4_hba.io_xri_max,
 		  lpfc_sli4_get_els_iocb_cnt(phba));
 	if (strlcat(buf, tmp, PAGE_SIZE) >= PAGE_SIZE)
-		goto rcu_unlock_buf_done;
+		goto buffer_done;
 
 	/* Port state is only one of two values for now. */
 	if (localport->port_id)
@@ -371,15 +369,17 @@ lpfc_nvme_info_show(struct device *dev, struct device_attribute *attr,
 		  wwn_to_u64(vport->fc_nodename.u.wwn),
 		  localport->port_id, statep);
 	if (strlcat(buf, tmp, PAGE_SIZE) >= PAGE_SIZE)
-		goto rcu_unlock_buf_done;
+		goto buffer_done;
+
+	spin_lock_irq(shost->host_lock);
 
 	list_for_each_entry(ndlp, &vport->fc_nodes, nlp_listp) {
 		nrport = NULL;
-		spin_lock_irqsave(&vport->phba->hbalock, iflags);
+		spin_lock(&vport->phba->hbalock);
 		rport = lpfc_ndlp_get_nrport(ndlp);
 		if (rport)
 			nrport = rport->remoteport;
-		spin_unlock_irqrestore(&vport->phba->hbalock, iflags);
+		spin_unlock(&vport->phba->hbalock);
 		if (!nrport)
 			continue;
 
@@ -398,39 +398,39 @@ lpfc_nvme_info_show(struct device *dev, struct device_attribute *attr,
 
 		/* Tab in to show lport ownership. */
 		if (strlcat(buf, "NVME RPORT       ", PAGE_SIZE) >= PAGE_SIZE)
-			goto rcu_unlock_buf_done;
+			goto unlock_buf_done;
 		if (phba->brd_no >= 10) {
 			if (strlcat(buf, " ", PAGE_SIZE) >= PAGE_SIZE)
-				goto rcu_unlock_buf_done;
+				goto unlock_buf_done;
 		}
 
 		scnprintf(tmp, sizeof(tmp), "WWPN x%llx ",
 			  nrport->port_name);
 		if (strlcat(buf, tmp, PAGE_SIZE) >= PAGE_SIZE)
-			goto rcu_unlock_buf_done;
+			goto unlock_buf_done;
 
 		scnprintf(tmp, sizeof(tmp), "WWNN x%llx ",
 			  nrport->node_name);
 		if (strlcat(buf, tmp, PAGE_SIZE) >= PAGE_SIZE)
-			goto rcu_unlock_buf_done;
+			goto unlock_buf_done;
 
 		scnprintf(tmp, sizeof(tmp), "DID x%06x ",
 			  nrport->port_id);
 		if (strlcat(buf, tmp, PAGE_SIZE) >= PAGE_SIZE)
-			goto rcu_unlock_buf_done;
+			goto unlock_buf_done;
 
 		/* An NVME rport can have multiple roles. */
 		if (nrport->port_role & FC_PORT_ROLE_NVME_INITIATOR) {
 			if (strlcat(buf, "INITIATOR ", PAGE_SIZE) >= PAGE_SIZE)
-				goto rcu_unlock_buf_done;
+				goto unlock_buf_done;
 		}
 		if (nrport->port_role & FC_PORT_ROLE_NVME_TARGET) {
 			if (strlcat(buf, "TARGET ", PAGE_SIZE) >= PAGE_SIZE)
-				goto rcu_unlock_buf_done;
+				goto unlock_buf_done;
 		}
 		if (nrport->port_role & FC_PORT_ROLE_NVME_DISCOVERY) {
 			if (strlcat(buf, "DISCSRVC ", PAGE_SIZE) >= PAGE_SIZE)
-				goto rcu_unlock_buf_done;
+				goto unlock_buf_done;
 		}
 		if (nrport->port_role & ~(FC_PORT_ROLE_NVME_INITIATOR |
 					  FC_PORT_ROLE_NVME_TARGET |
@@ -438,14 +438,14 @@ lpfc_nvme_info_show(struct device *dev, struct device_attribute *attr,
 			scnprintf(tmp, sizeof(tmp), "UNKNOWN ROLE x%x",
 				  nrport->port_role);
 			if (strlcat(buf, tmp, PAGE_SIZE) >= PAGE_SIZE)
-				goto rcu_unlock_buf_done;
+				goto unlock_buf_done;
 		}
 
 		scnprintf(tmp, sizeof(tmp), "%s\n", statep);
 		if (strlcat(buf, tmp, PAGE_SIZE) >= PAGE_SIZE)
-			goto rcu_unlock_buf_done;
+			goto unlock_buf_done;
 	}
-	rcu_read_unlock();
+	spin_unlock_irq(shost->host_lock);
 
 	if (!lport)
 		goto buffer_done;
@@ -505,11 +505,11 @@ lpfc_nvme_info_show(struct device *dev, struct device_attribute *attr,
 		  atomic_read(&lport->cmpl_fcp_err));
 	strlcat(buf, tmp, PAGE_SIZE);
 
-	/* RCU is already unlocked. */
+	/* host_lock is already unlocked. */
 	goto buffer_done;
 
- rcu_unlock_buf_done:
-	rcu_read_unlock();
+ unlock_buf_done:
+	spin_unlock_irq(shost->host_lock);
 
  buffer_done:
 	len = strnlen(buf, PAGE_SIZE);
-- 
2.13.7


  parent reply	other threads:[~2019-11-05  0:57 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-05  0:56 [PATCH 00/11] lpfc: Update lpfc to revision 12.6.0.1 James Smart
2019-11-05  0:56 ` [PATCH 01/11] lpfc: Fix duplicate unreg_rpi error in port offline flow James Smart
2019-11-05  0:56 ` [PATCH 02/11] lpfc: Fix configuration of BB credit recovery in service parameters James Smart
2019-11-05  0:57 ` James Smart [this message]
2019-11-05  0:57 ` [PATCH 04/11] lpfc: Fix unexpected error messages during RSCN handling James Smart
2019-11-05  0:57 ` [PATCH 05/11] lpfc: Fix dynamic fw log enablement check James Smart
2019-11-05  0:57 ` [PATCH 06/11] lpfc: Sync with FC-NVMe-2 SLER change to require Conf with SLER James Smart
2019-11-05  0:57 ` [PATCH 07/11] lpfc: Clarify FAWNN error message James Smart
2019-11-05  0:57 ` [PATCH 08/11] lpfc: Add registration for CPU Offline/Online events James Smart
2019-11-05  0:57 ` [PATCH 09/11] lpfc: Change default IRQ model on AMD architectures James Smart
2019-11-05  0:57 ` [PATCH 10/11] lpfc: Add enablement of multiple adapter dumps James Smart
2019-11-05  0:57 ` [PATCH 11/11] lpfc: Update lpfc version to 12.6.0.1 James Smart
2019-11-06  4:45 ` [PATCH 00/11] lpfc: Update lpfc to revision 12.6.0.1 Martin K. Petersen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191105005708.7399-4-jsmart2021@gmail.com \
    --to=jsmart2021@gmail.com \
    --cc=dick.kennedy@broadcom.com \
    --cc=linux-scsi@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.