This is a note to let you know that I've just added the patch titled scsi: ses: don't ask for diagnostic pages repeatedly during probe to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: scsi-ses-don-t-ask-for-diagnostic-pages-repeatedly-during-probe.patch and it can be found in the queue-4.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Fri Mar 16 15:11:07 CET 2018 From: Li Dongyang <dongyang.li@xxxxxxxxxx> Date: Tue, 14 Nov 2017 10:48:04 +1100 Subject: scsi: ses: don't ask for diagnostic pages repeatedly during probe From: Li Dongyang <dongyang.li@xxxxxxxxxx> [ Upstream commit 9c0a50022b8ac7e863e6ec8342fa476fe5d1d75c ] We are testing if there is a match with the ses device in a loop by calling ses_match_to_enclosure(), which will issue scsi receive diagnostics commands to the ses device for every device on the same host. On one of our boxes with 840 disks, it takes a long time to load the driver: [root@g1b-oss06 ~]# time modprobe ses real 40m48.247s user 0m0.001s sys 0m0.196s With the patch: [root@g1b-oss06 ~]# time modprobe ses real 0m17.915s user 0m0.008s sys 0m0.053s Note that we still need to refresh page 10 when we see a new disk to create the link. Signed-off-by: Li Dongyang <dongyang.li@xxxxxxxxxx> Tested-by: Jason Ozolins <jason.ozolins@xxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/ses.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) --- a/drivers/scsi/ses.c +++ b/drivers/scsi/ses.c @@ -615,13 +615,16 @@ static void ses_enclosure_data_process(s } static void ses_match_to_enclosure(struct enclosure_device *edev, - struct scsi_device *sdev) + struct scsi_device *sdev, + int refresh) { + struct scsi_device *edev_sdev = to_scsi_device(edev->edev.parent); struct efd efd = { .addr = 0, }; - ses_enclosure_data_process(edev, to_scsi_device(edev->edev.parent), 0); + if (refresh) + ses_enclosure_data_process(edev, edev_sdev, 0); if (scsi_is_sas_rphy(sdev->sdev_target->dev.parent)) efd.addr = sas_get_address(sdev); @@ -652,7 +655,7 @@ static int ses_intf_add(struct device *c struct enclosure_device *prev = NULL; while ((edev = enclosure_find(&sdev->host->shost_gendev, prev)) != NULL) { - ses_match_to_enclosure(edev, sdev); + ses_match_to_enclosure(edev, sdev, 1); prev = edev; } return -ENODEV; @@ -768,7 +771,7 @@ page2_not_supported: shost_for_each_device(tmp_sdev, sdev->host) { if (tmp_sdev->lun != 0 || scsi_device_enclosure(tmp_sdev)) continue; - ses_match_to_enclosure(edev, tmp_sdev); + ses_match_to_enclosure(edev, tmp_sdev, 0); } return 0; Patches currently in stable-queue which might be from dongyang.li@xxxxxxxxxx are queue-4.15/scsi-ses-don-t-ask-for-diagnostic-pages-repeatedly-during-probe.patch