From 9f4aa52387c68049403b59939df5c0dd8e3872cc Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Tue, 14 Jul 2020 22:03:26 +0200 Subject: [PATCH] s390/dasd: fix inability to use DASD with DIAG driver During initialization of the DASD DIAG driver a request is issued that has a bio structure that resides on the stack. With virtually mapped kernel stacks this bio address might be in virtual storage which is unsuitable for usage with the diag250 call. In this case the device can not be set online using the DIAG discipline and fails with -EOPNOTSUP. In the system journal the following error message is presented: dasd: X.X.XXXX Setting the DASD online with discipline DIAG failed with rc=-95 Fix by allocating the bio structure instead of having it on the stack. Fixes: ce3dc447493f ("s390: add support for virtually mapped kernel stacks") Signed-off-by: Stefan Haberland Reviewed-by: Peter Oberparleiter Cc: stable@vger.kernel.org #4.20 Signed-off-by: Jens Axboe --- drivers/s390/block/dasd_diag.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c index facb588d09e4..069d6b39cacf 100644 --- a/drivers/s390/block/dasd_diag.c +++ b/drivers/s390/block/dasd_diag.c @@ -319,7 +319,7 @@ dasd_diag_check_device(struct dasd_device *device) struct dasd_diag_characteristics *rdc_data; struct vtoc_cms_label *label; struct dasd_block *block; - struct dasd_diag_bio bio; + struct dasd_diag_bio *bio; unsigned int sb, bsize; blocknum_t end_block; int rc; @@ -395,29 +395,36 @@ dasd_diag_check_device(struct dasd_device *device) rc = -ENOMEM; goto out; } + bio = kzalloc(sizeof(*bio), GFP_KERNEL); + if (bio == NULL) { + DBF_DEV_EVENT(DBF_WARNING, device, "%s", + "No memory to allocate initialization bio"); + rc = -ENOMEM; + goto out_label; + } rc = 0; end_block = 0; /* try all sizes - needed for ECKD devices */ for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) { mdsk_init_io(device, bsize, 0, &end_block); - memset(&bio, 0, sizeof (struct dasd_diag_bio)); - bio.type = MDSK_READ_REQ; - bio.block_number = private->pt_block + 1; - bio.buffer = label; + memset(bio, 0, sizeof(*bio)); + bio->type = MDSK_READ_REQ; + bio->block_number = private->pt_block + 1; + bio->buffer = label; memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io)); private->iob.dev_nr = rdc_data->dev_nr; private->iob.key = 0; private->iob.flags = 0; /* do synchronous io */ private->iob.block_count = 1; private->iob.interrupt_params = 0; - private->iob.bio_list = &bio; + private->iob.bio_list = bio; private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; rc = dia250(&private->iob, RW_BIO); if (rc == 3) { pr_warn("%s: A 64-bit DIAG call failed\n", dev_name(&device->cdev->dev)); rc = -EOPNOTSUPP; - goto out_label; + goto out_bio; } mdsk_term_io(device); if (rc == 0) @@ -427,7 +434,7 @@ dasd_diag_check_device(struct dasd_device *device) pr_warn("%s: Accessing the DASD failed because of an incorrect format (rc=%d)\n", dev_name(&device->cdev->dev), rc); rc = -EIO; - goto out_label; + goto out_bio; } /* check for label block */ if (memcmp(label->label_id, DASD_DIAG_CMS1, @@ -457,6 +464,8 @@ dasd_diag_check_device(struct dasd_device *device) (rc == 4) ? ", read-only device" : ""); rc = 0; } +out_bio: + kfree(bio); out_label: free_page((long) label); out: