All of lore.kernel.org
 help / color / mirror / Atom feed
From: Bob Pearson <rpearsonhpe@gmail.com>
To: Bart Van Assche <bvanassche@acm.org>,
	Jason Gunthorpe <jgg@nvidia.com>,
	Bernard Metzler <bmt@zurich.ibm.com>,
	Zhu Yanjun <zyjzyj2000@gmail.com>,
	"linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>
Cc: Yi Zhang <yi.zhang@redhat.com>, Douglas Gilbert <dgilbert@interlog.com>
Subject: Re: Apparent regression in blktests since 5.18-rc1+
Date: Tue, 17 May 2022 15:59:19 -0500	[thread overview]
Message-ID: <b656d7b5-3752-eea3-aa00-40f50970bdc6@gmail.com> (raw)
In-Reply-To: <88e9b45d-e7cd-45ce-ad12-d1ec8e238bc8@acm.org>

[-- Attachment #1: Type: text/plain, Size: 1406 bytes --]

On 5/17/22 15:44, Bart Van Assche wrote:
> On 5/17/22 17:21, Bob Pearson wrote:
>> Thanks Bart. I was able to follow your steps above. But unfortunately not much has changed.
>> I still see hangs in siw (with no code changes by me) and also in rxe (but here I have
>> fixed some lockdep warnings so it will run in a debug kernel.) There are two test cases that
>> cause the most problems. srp/002 and srp/011. 011 always fails solidly. 002 sometimes hangs and
>> sometimes completes but with failed status. The rest of the tests all pass.
>>
>> Both tests hang at a line that looks like
>>     scsi host6: ib_srp: Already connected to target port with id_ext=...
>>
>> When 002 completes but fails there are 14 second gaps at some of the same lines in the trace.
>> This has the feel of the earlier problem with the 3 minute timeout that was fixed by the
>> patch (revert ... scsi_debug.c) that you sent and is applied here.
>>
>> I really don't know how to make progress here. If anyone knows what is happening at the
>> already connected lines let me know. They seem normal except for the long gaps and hangs
>> when they occur.
> 
> How about sharing the kernel config file that you are using in your tests such that I can try to reproduce the behavior that you are observing?
> 
> Thanks,
> 
> Bart.

I built the kernel from rdma-rc and applied scsi-debug.patch (yours) and tempoirary-AH.patch

Bob

[-- Attachment #2: scsi-debug.patch --]
[-- Type: text/x-patch, Size: 16452 bytes --]

From: Bart Van Assche <bvanassche@acm.org>
To: "Martin K . Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org, Bart Van Assche <bvanassche@acm.org>,
	Yi Zhang <yi.zhang@redhat.com>,
	Douglas Gilbert <dgilbert@interlog.com>,
	Bob Pearson <rpearsonhpe@gmail.com>,
	"James E.J. Bottomley" <jejb@linux.ibm.com>
Subject: [PATCH] Revert "scsi: scsi_debug: Address races following module load"
Date: Fri,  8 Apr 2022 21:37:03 -0700	[thread overview]
Message-ID: <20220409043704.28573-1-bvanassche@acm.org> (raw)

Revert the patch mentioned in the subject since it blocks I/O after
module unload has started while this is a legitimate use case. For e.g.
blktests test case srp/001 that patch causes a command timeout to be
triggered for the following call stack:

__schedule+0x4c3/0xd20
schedule+0x82/0x110
schedule_timeout+0x122/0x200
io_schedule_timeout+0x7b/0xc0
__wait_for_common+0x2bc/0x380
wait_for_completion_io_timeout+0x1d/0x20
blk_execute_rq+0x1db/0x200
__scsi_execute+0x1fb/0x310
sd_sync_cache+0x155/0x2c0 [sd_mod]
sd_shutdown+0xbb/0x190 [sd_mod]
sd_remove+0x5b/0x80 [sd_mod]
device_remove+0x9a/0xb0
device_release_driver_internal+0x2c5/0x360
device_release_driver+0x12/0x20
bus_remove_device+0x1aa/0x270
device_del+0x2d4/0x640
__scsi_remove_device+0x168/0x1a0
scsi_forget_host+0xa8/0xb0
scsi_remove_host+0x9b/0x150
sdebug_driver_remove+0x3d/0x140 [scsi_debug]
device_remove+0x6f/0xb0
device_release_driver_internal+0x2c5/0x360
device_release_driver+0x12/0x20
bus_remove_device+0x1aa/0x270
device_del+0x2d4/0x640
device_unregister+0x18/0x70
sdebug_do_remove_host+0x138/0x180 [scsi_debug]
scsi_debug_exit+0x45/0xd5 [scsi_debug]
__do_sys_delete_module.constprop.0+0x210/0x320
__x64_sys_delete_module+0x1f/0x30
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported-by: Yi Zhang <yi.zhang@redhat.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Yi Zhang <yi.zhang@redhat.com>
Cc: Bob Pearson <rpearsonhpe@gmail.com>
Fixes: 2aad3cd85370 ("scsi: scsi_debug: Address races following module load"; )
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 drivers/scsi/scsi_debug.c | 197 ++++++++++----------------------------
 1 file changed, 51 insertions(+), 146 deletions(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index c607755cce00..db6f4b96606c 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -32,7 +32,6 @@
 #include <linux/blkdev.h>
 #include <linux/crc-t10dif.h>
 #include <linux/spinlock.h>
-#include <linux/mutex.h>
 #include <linux/interrupt.h>
 #include <linux/atomic.h>
 #include <linux/hrtimer.h>
@@ -732,9 +731,7 @@ static const struct opcode_info_t opcode_info_arr[SDEB_I_LAST_ELEM_P1 + 1] = {
 	    {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
 };
 
-static atomic_t sdebug_num_hosts;
-static DEFINE_MUTEX(add_host_mutex);
-
+static int sdebug_num_hosts;
 static int sdebug_add_host = DEF_NUM_HOST;  /* in sysfs this is relative */
 static int sdebug_ato = DEF_ATO;
 static int sdebug_cdb_len = DEF_CDB_LEN;
@@ -781,7 +778,6 @@ static int sdebug_uuid_ctl = DEF_UUID_CTL;
 static bool sdebug_random = DEF_RANDOM;
 static bool sdebug_per_host_store = DEF_PER_HOST_STORE;
 static bool sdebug_removable = DEF_REMOVABLE;
-static bool sdebug_deflect_incoming;
 static bool sdebug_clustering;
 static bool sdebug_host_lock = DEF_HOST_LOCK;
 static bool sdebug_strict = DEF_STRICT;
@@ -5122,10 +5118,6 @@ static int scsi_debug_slave_configure(struct scsi_device *sdp)
 		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
 	if (sdp->host->max_cmd_len != SDEBUG_MAX_CMD_LEN)
 		sdp->host->max_cmd_len = SDEBUG_MAX_CMD_LEN;
-	if (smp_load_acquire(&sdebug_deflect_incoming)) {
-		pr_info("Exit early due to deflect_incoming\n");
-		return 1;
-	}
 	if (devip == NULL) {
 		devip = find_build_dev_info(sdp);
 		if (devip == NULL)
@@ -5211,7 +5203,7 @@ static bool stop_queued_cmnd(struct scsi_cmnd *cmnd)
 }
 
 /* Deletes (stops) timers or work queues of all queued commands */
-static void stop_all_queued(bool done_with_no_conn)
+static void stop_all_queued(void)
 {
 	unsigned long iflags;
 	int j, k;
@@ -5220,15 +5212,13 @@ static void stop_all_queued(bool done_with_no_conn)
 	struct sdebug_queued_cmd *sqcp;
 	struct sdebug_dev_info *devip;
 	struct sdebug_defer *sd_dp;
-	struct scsi_cmnd *scp;
 
 	for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) {
 		spin_lock_irqsave(&sqp->qc_lock, iflags);
 		for (k = 0; k < SDEBUG_CANQUEUE; ++k) {
 			if (test_bit(k, sqp->in_use_bm)) {
 				sqcp = &sqp->qc_arr[k];
-				scp = sqcp->a_cmnd;
-				if (!scp)
+				if (sqcp->a_cmnd == NULL)
 					continue;
 				devip = (struct sdebug_dev_info *)
 					sqcp->a_cmnd->device->hostdata;
@@ -5243,10 +5233,6 @@ static void stop_all_queued(bool done_with_no_conn)
 					l_defer_t = SDEB_DEFER_NONE;
 				spin_unlock_irqrestore(&sqp->qc_lock, iflags);
 				stop_qc_helper(sd_dp, l_defer_t);
-				if (done_with_no_conn && l_defer_t != SDEB_DEFER_NONE) {
-					scp->result = DID_NO_CONNECT << 16;
-					scsi_done(scp);
-				}
 				clear_bit(k, sqp->in_use_bm);
 				spin_lock_irqsave(&sqp->qc_lock, iflags);
 			}
@@ -5389,7 +5375,7 @@ static int scsi_debug_host_reset(struct scsi_cmnd *SCpnt)
 		}
 	}
 	spin_unlock(&sdebug_host_list_lock);
-	stop_all_queued(false);
+	stop_all_queued();
 	if (SDEBUG_OPT_RESET_NOISE & sdebug_opts)
 		sdev_printk(KERN_INFO, SCpnt->device,
 			    "%s: %d device(s) found\n", __func__, k);
@@ -5449,50 +5435,13 @@ static void sdebug_build_parts(unsigned char *ramp, unsigned long store_size)
 	}
 }
 
-static void sdeb_block_all_queues(void)
-{
-	int j;
-	struct sdebug_queue *sqp;
-
-	for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp)
-		atomic_set(&sqp->blocked, (int)true);
-}
-
-static void sdeb_unblock_all_queues(void)
+static void block_unblock_all_queues(bool block)
 {
 	int j;
 	struct sdebug_queue *sqp;
 
 	for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp)
-		atomic_set(&sqp->blocked, (int)false);
-}
-
-static void
-sdeb_add_n_hosts(int num_hosts)
-{
-	if (num_hosts < 1)
-		return;
-	do {
-		bool found;
-		unsigned long idx;
-		struct sdeb_store_info *sip;
-		bool want_phs = (sdebug_fake_rw == 0) && sdebug_per_host_store;
-
-		found = false;
-		if (want_phs) {
-			xa_for_each_marked(per_store_ap, idx, sip, SDEB_XA_NOT_IN_USE) {
-				sdeb_most_recent_idx = (int)idx;
-				found = true;
-				break;
-			}
-			if (found)	/* re-use case */
-				sdebug_add_host_helper((int)idx);
-			else
-				sdebug_do_add_host(true	/* make new store */);
-		} else {
-			sdebug_do_add_host(false);
-		}
-	} while (--num_hosts);
+		atomic_set(&sqp->blocked, (int)block);
 }
 
 /* Adjust (by rounding down) the sdebug_cmnd_count so abs(every_nth)-1
@@ -5505,10 +5454,10 @@ static void tweak_cmnd_count(void)
 	modulo = abs(sdebug_every_nth);
 	if (modulo < 2)
 		return;
-	sdeb_block_all_queues();
+	block_unblock_all_queues(true);
 	count = atomic_read(&sdebug_cmnd_count);
 	atomic_set(&sdebug_cmnd_count, (count / modulo) * modulo);
-	sdeb_unblock_all_queues();
+	block_unblock_all_queues(false);
 }
 
 static void clear_queue_stats(void)
@@ -5526,15 +5475,6 @@ static bool inject_on_this_cmd(void)
 	return (atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth)) == 0;
 }
 
-static int process_deflect_incoming(struct scsi_cmnd *scp)
-{
-	u8 opcode = scp->cmnd[0];
-
-	if (opcode == SYNCHRONIZE_CACHE || opcode == SYNCHRONIZE_CACHE_16)
-		return 0;
-	return DID_NO_CONNECT << 16;
-}
-
 #define INCLUSIVE_TIMING_MAX_NS 1000000		/* 1 millisecond */
 
 /* Complete the processing of the thread that queued a SCSI command to this
@@ -5544,7 +5484,8 @@ static int process_deflect_incoming(struct scsi_cmnd *scp)
  */
 static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
 			 int scsi_result,
-			 int (*pfp)(struct scsi_cmnd *, struct sdebug_dev_info *),
+			 int (*pfp)(struct scsi_cmnd *,
+				    struct sdebug_dev_info *),
 			 int delta_jiff, int ndelay)
 {
 	bool new_sd_dp;
@@ -5565,27 +5506,13 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
 	}
 	sdp = cmnd->device;
 
-	if (delta_jiff == 0) {
-		sqp = get_queue(cmnd);
-		if (atomic_read(&sqp->blocked)) {
-			if (smp_load_acquire(&sdebug_deflect_incoming))
-				return process_deflect_incoming(cmnd);
-			else
-				return SCSI_MLQUEUE_HOST_BUSY;
-		}
+	if (delta_jiff == 0)
 		goto respond_in_thread;
-	}
 
 	sqp = get_queue(cmnd);
 	spin_lock_irqsave(&sqp->qc_lock, iflags);
 	if (unlikely(atomic_read(&sqp->blocked))) {
 		spin_unlock_irqrestore(&sqp->qc_lock, iflags);
-		if (smp_load_acquire(&sdebug_deflect_incoming)) {
-			scsi_result = process_deflect_incoming(cmnd);
-			goto respond_in_thread;
-		}
-		if (sdebug_verbose)
-			pr_info("blocked --> SCSI_MLQUEUE_HOST_BUSY\n");
 		return SCSI_MLQUEUE_HOST_BUSY;
 	}
 	num_in_q = atomic_read(&devip->num_in_q);
@@ -5774,12 +5701,8 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
 respond_in_thread:	/* call back to mid-layer using invocation thread */
 	cmnd->result = pfp != NULL ? pfp(cmnd, devip) : 0;
 	cmnd->result &= ~SDEG_RES_IMMED_MASK;
-	if (cmnd->result == 0 && scsi_result != 0) {
+	if (cmnd->result == 0 && scsi_result != 0)
 		cmnd->result = scsi_result;
-		if (sdebug_verbose)
-			pr_info("respond_in_thread: tag=0x%x, scp->result=0x%x\n",
-				blk_mq_unique_tag(scsi_cmd_to_rq(cmnd)), scsi_result);
-	}
 	scsi_done(cmnd);
 	return 0;
 }
@@ -6064,7 +5987,7 @@ static ssize_t delay_store(struct device_driver *ddp, const char *buf,
 			int j, k;
 			struct sdebug_queue *sqp;
 
-			sdeb_block_all_queues();
+			block_unblock_all_queues(true);
 			for (j = 0, sqp = sdebug_q_arr; j < submit_queues;
 			     ++j, ++sqp) {
 				k = find_first_bit(sqp->in_use_bm,
@@ -6078,7 +6001,7 @@ static ssize_t delay_store(struct device_driver *ddp, const char *buf,
 				sdebug_jdelay = jdelay;
 				sdebug_ndelay = 0;
 			}
-			sdeb_unblock_all_queues();
+			block_unblock_all_queues(false);
 		}
 		return res;
 	}
@@ -6104,7 +6027,7 @@ static ssize_t ndelay_store(struct device_driver *ddp, const char *buf,
 			int j, k;
 			struct sdebug_queue *sqp;
 
-			sdeb_block_all_queues();
+			block_unblock_all_queues(true);
 			for (j = 0, sqp = sdebug_q_arr; j < submit_queues;
 			     ++j, ++sqp) {
 				k = find_first_bit(sqp->in_use_bm,
@@ -6119,7 +6042,7 @@ static ssize_t ndelay_store(struct device_driver *ddp, const char *buf,
 				sdebug_jdelay = ndelay  ? JDELAY_OVERRIDDEN
 							: DEF_JDELAY;
 			}
-			sdeb_unblock_all_queues();
+			block_unblock_all_queues(false);
 		}
 		return res;
 	}
@@ -6433,7 +6356,7 @@ static ssize_t max_queue_store(struct device_driver *ddp, const char *buf,
 	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n > 0) &&
 	    (n <= SDEBUG_CANQUEUE) &&
 	    (sdebug_host_max_queue == 0)) {
-		sdeb_block_all_queues();
+		block_unblock_all_queues(true);
 		k = 0;
 		for (j = 0, sqp = sdebug_q_arr; j < submit_queues;
 		     ++j, ++sqp) {
@@ -6448,7 +6371,7 @@ static ssize_t max_queue_store(struct device_driver *ddp, const char *buf,
 			atomic_set(&retired_max_queue, k + 1);
 		else
 			atomic_set(&retired_max_queue, 0);
-		sdeb_unblock_all_queues();
+		block_unblock_all_queues(false);
 		return count;
 	}
 	return -EINVAL;
@@ -6537,48 +6460,43 @@ static DRIVER_ATTR_RW(virtual_gb);
 static ssize_t add_host_show(struct device_driver *ddp, char *buf)
 {
 	/* absolute number of hosts currently active is what is shown */
-	return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&sdebug_num_hosts));
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_num_hosts);
 }
 
-/*
- * Accept positive and negative values. Hex values (only positive) may be prefixed by '0x'.
- * To remove all hosts use a large negative number (e.g. -9999). The value 0 does nothing.
- * Returns -EBUSY if another add_host sysfs invocation is active.
- */
 static ssize_t add_host_store(struct device_driver *ddp, const char *buf,
 			      size_t count)
 {
+	bool found;
+	unsigned long idx;
+	struct sdeb_store_info *sip;
+	bool want_phs = (sdebug_fake_rw == 0) && sdebug_per_host_store;
 	int delta_hosts;
 
-	if (count == 0 || kstrtoint(buf, 0, &delta_hosts))
+	if (sscanf(buf, "%d", &delta_hosts) != 1)
 		return -EINVAL;
-	if (sdebug_verbose)
-		pr_info("prior num_hosts=%d, num_to_add=%d\n",
-			atomic_read(&sdebug_num_hosts), delta_hosts);
-	if (delta_hosts == 0)
-		return count;
-	if (mutex_trylock(&add_host_mutex) == 0)
-		return -EBUSY;
 	if (delta_hosts > 0) {
-		sdeb_add_n_hosts(delta_hosts);
-	} else if (delta_hosts < 0) {
-		smp_store_release(&sdebug_deflect_incoming, true);
-		sdeb_block_all_queues();
-		if (delta_hosts >= atomic_read(&sdebug_num_hosts))
-			stop_all_queued(true);
 		do {
-			if (atomic_read(&sdebug_num_hosts) < 1) {
-				free_all_queued();
-				break;
+			found = false;
+			if (want_phs) {
+				xa_for_each_marked(per_store_ap, idx, sip,
+						   SDEB_XA_NOT_IN_USE) {
+					sdeb_most_recent_idx = (int)idx;
+					found = true;
+					break;
+				}
+				if (found)	/* re-use case */
+					sdebug_add_host_helper((int)idx);
+				else
+					sdebug_do_add_host(true);
+			} else {
+				sdebug_do_add_host(false);
 			}
+		} while (--delta_hosts);
+	} else if (delta_hosts < 0) {
+		do {
 			sdebug_do_remove_host(false);
 		} while (++delta_hosts);
-		sdeb_unblock_all_queues();
-		smp_store_release(&sdebug_deflect_incoming, false);
 	}
-	mutex_unlock(&add_host_mutex);
-	if (sdebug_verbose)
-		pr_info("post num_hosts=%d\n", atomic_read(&sdebug_num_hosts));
 	return count;
 }
 static DRIVER_ATTR_RW(add_host);
@@ -7089,10 +7007,6 @@ static int __init scsi_debug_init(void)
 	sdebug_add_host = 0;
 
 	for (k = 0; k < hosts_to_add; k++) {
-		if (smp_load_acquire(&sdebug_deflect_incoming)) {
-			pr_info("exit early as sdebug_deflect_incoming is set\n");
-			return 0;
-		}
 		if (want_store && k == 0) {
 			ret = sdebug_add_host_helper(idx);
 			if (ret < 0) {
@@ -7110,12 +7024,8 @@ static int __init scsi_debug_init(void)
 		}
 	}
 	if (sdebug_verbose)
-		pr_info("built %d host(s)\n", atomic_read(&sdebug_num_hosts));
+		pr_info("built %d host(s)\n", sdebug_num_hosts);
 
-	/*
-	 * Even though all the hosts have been established, due to async device (LU) scanning
-	 * by the scsi mid-level, there may still be devices (LUs) being set up.
-	 */
 	return 0;
 
 bus_unreg:
@@ -7131,17 +7041,12 @@ static int __init scsi_debug_init(void)
 
 static void __exit scsi_debug_exit(void)
 {
-	int k;
+	int k = sdebug_num_hosts;
 
-	/* Possible race with LUs still being set up; stop them asap */
-	sdeb_block_all_queues();
-	smp_store_release(&sdebug_deflect_incoming, true);
-	stop_all_queued(false);
-	for (k = 0; atomic_read(&sdebug_num_hosts) > 0; k++)
+	stop_all_queued();
+	for (; k; k--)
 		sdebug_do_remove_host(true);
 	free_all_queued();
-	if (sdebug_verbose)
-		pr_info("removed %d hosts\n", k);
 	driver_unregister(&sdebug_driverfs_driver);
 	bus_unregister(&pseudo_lld_bus);
 	root_device_unregister(pseudo_primary);
@@ -7311,13 +7216,13 @@ static int sdebug_add_host_helper(int per_host_idx)
 	sdbg_host->dev.bus = &pseudo_lld_bus;
 	sdbg_host->dev.parent = pseudo_primary;
 	sdbg_host->dev.release = &sdebug_release_adapter;
-	dev_set_name(&sdbg_host->dev, "adapter%d", atomic_read(&sdebug_num_hosts));
+	dev_set_name(&sdbg_host->dev, "adapter%d", sdebug_num_hosts);
 
 	error = device_register(&sdbg_host->dev);
 	if (error)
 		goto clean;
 
-	atomic_inc(&sdebug_num_hosts);
+	++sdebug_num_hosts;
 	return 0;
 
 clean:
@@ -7381,7 +7286,7 @@ static void sdebug_do_remove_host(bool the_end)
 		return;
 
 	device_unregister(&sdbg_host->dev);
-	atomic_dec(&sdebug_num_hosts);
+	--sdebug_num_hosts;
 }
 
 static int sdebug_change_qdepth(struct scsi_device *sdev, int qdepth)
@@ -7389,10 +7294,10 @@ static int sdebug_change_qdepth(struct scsi_device *sdev, int qdepth)
 	int num_in_q = 0;
 	struct sdebug_dev_info *devip;
 
-	sdeb_block_all_queues();
+	block_unblock_all_queues(true);
 	devip = (struct sdebug_dev_info *)sdev->hostdata;
 	if (NULL == devip) {
-		sdeb_unblock_all_queues();
+		block_unblock_all_queues(false);
 		return	-ENODEV;
 	}
 	num_in_q = atomic_read(&devip->num_in_q);
@@ -7411,7 +7316,7 @@ static int sdebug_change_qdepth(struct scsi_device *sdev, int qdepth)
 		sdev_printk(KERN_INFO, sdev, "%s: qdepth=%d, num_in_q=%d\n",
 			    __func__, qdepth, num_in_q);
 	}
-	sdeb_unblock_all_queues();
+	block_unblock_all_queues(false);
 	return sdev->queue_depth;
 }
 

[-- Attachment #3: 0001-RDMA-rxe-Temporary-AH-fix.patch --]
[-- Type: text/x-patch, Size: 2520 bytes --]

From cd71dc23c2331fc0195ef00022ad2e4284ceefff Mon Sep 17 00:00:00 2001
From: Bob Pearson <rpearsonhpe@gmail.com>
Date: Tue, 17 May 2022 15:37:34 -0500
Subject: [PATCH] RDMA/rxe: Temporary AH fix

Fix lockdep warnings in rxe_pool.c and kmalloc might sleep
in __xa_alloc_cyclic(). These will need to change when
read side locking is converted to RCU.

Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
---
 drivers/infiniband/sw/rxe/rxe_pool.c | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c
index 19b14826385b..5491b4340b0d 100644
--- a/drivers/infiniband/sw/rxe/rxe_pool.c
+++ b/drivers/infiniband/sw/rxe/rxe_pool.c
@@ -117,7 +117,9 @@ void rxe_pool_cleanup(struct rxe_pool *pool)
 
 void *rxe_alloc(struct rxe_pool *pool)
 {
+	struct xarray *xa = &pool->xa;
 	struct rxe_pool_elem *elem;
+	unsigned long flags;
 	void *obj;
 	int err;
 
@@ -137,8 +139,10 @@ void *rxe_alloc(struct rxe_pool *pool)
 	elem->obj = obj;
 	kref_init(&elem->ref_cnt);
 
-	err = xa_alloc_cyclic(&pool->xa, &elem->index, elem, pool->limit,
-			      &pool->next, GFP_KERNEL);
+	xa_lock_irqsave(xa, flags);
+	err = __xa_alloc_cyclic(xa, &elem->index, elem, pool->limit,
+			      &pool->next, GFP_ATOMIC);
+	xa_unlock_irqrestore(xa, flags);
 	if (err)
 		goto err_free;
 
@@ -153,6 +157,8 @@ void *rxe_alloc(struct rxe_pool *pool)
 
 int __rxe_add_to_pool(struct rxe_pool *pool, struct rxe_pool_elem *elem)
 {
+	struct xarray *xa = &pool->xa;
+	unsigned long flags;
 	int err;
 
 	if (WARN_ON(pool->type == RXE_TYPE_MR))
@@ -165,8 +171,10 @@ int __rxe_add_to_pool(struct rxe_pool *pool, struct rxe_pool_elem *elem)
 	elem->obj = (u8 *)elem - pool->elem_offset;
 	kref_init(&elem->ref_cnt);
 
-	err = xa_alloc_cyclic(&pool->xa, &elem->index, elem, pool->limit,
-			      &pool->next, GFP_KERNEL);
+	xa_lock_irqsave(xa, flags);
+	err = __xa_alloc_cyclic(xa, &elem->index, elem, pool->limit,
+			      &pool->next, GFP_ATOMIC);
+	xa_unlock_irqrestore(xa, flags);
 	if (err)
 		goto err_cnt;
 
@@ -199,8 +207,12 @@ static void rxe_elem_release(struct kref *kref)
 {
 	struct rxe_pool_elem *elem = container_of(kref, typeof(*elem), ref_cnt);
 	struct rxe_pool *pool = elem->pool;
+	struct xarray *xa = &pool->xa;
+	unsigned long flags;
 
-	xa_erase(&pool->xa, elem->index);
+	xa_lock_irqsave(xa, flags);
+	__xa_erase(xa, elem->index);
+	xa_unlock_irqrestore(xa, flags);
 
 	if (pool->cleanup)
 		pool->cleanup(elem);
-- 
2.34.1


  parent reply	other threads:[~2022-05-17 20:59 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-06 18:11 Apparent regression in blktests since 5.18-rc1+ Bob Pearson
2022-05-07  0:10 ` Bart Van Assche
2022-05-07  0:29   ` Yanjun Zhu
2022-05-07  1:29     ` Jason Gunthorpe
2022-05-07  1:55       ` Yanjun Zhu
2022-05-07 13:43         ` Bob Pearson
2022-05-08  4:13           ` Bart Van Assche
2022-05-10 15:24             ` Pearson, Robert B
2022-05-12 21:57             ` Bob Pearson
2022-05-12 22:25               ` Bart Van Assche
2022-05-13  0:41                 ` Bob Pearson
2022-05-13  3:40                   ` Bart Van Assche
2022-05-17 15:21                     ` Bob Pearson
2022-05-17 20:44                       ` Bart Van Assche
2022-05-17 20:54                         ` Bob Pearson
2022-05-17 20:59                         ` Bob Pearson [this message]
2022-05-08  8:43         ` Yanjun Zhu
2022-05-09  8:01       ` Zhu Yanjun
2022-05-09 11:52         ` Jason Gunthorpe
2022-05-09 12:31           ` Yanjun Zhu
2022-05-09 12:33             ` Jason Gunthorpe
2022-05-09 12:42               ` Yanjun Zhu
2022-05-07 13:40     ` Bob Pearson
2022-05-09  6:56 ` Thorsten Leemhuis
2022-05-10  3:53   ` Bart Van Assche

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=b656d7b5-3752-eea3-aa00-40f50970bdc6@gmail.com \
    --to=rpearsonhpe@gmail.com \
    --cc=bmt@zurich.ibm.com \
    --cc=bvanassche@acm.org \
    --cc=dgilbert@interlog.com \
    --cc=jgg@nvidia.com \
    --cc=linux-rdma@vger.kernel.org \
    --cc=yi.zhang@redhat.com \
    --cc=zyjzyj2000@gmail.com \
    /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.