File s390-tools-sles15sp3-zipl-fix-4k-scsi-ipl.patch of Package s390-tools.28664

Subject: [PATCH] [BZ 191696] zipl: fix reading 4k disk's geometry
From: Stefan Haberland <sth@linux.ibm.com>

Description:   zipl: fix IPL on 4K SCSI disks
Symptom:       IPL is not working when bootloader is installed
               on a SCSI disk with 4k physical blocksize without using
               a devicemapper target.
Problem:       The getgeo ioctl that is used reports the partition
               start in multiple of 512 byte sectors but the blocksize
               that is used is the physical blocksize of 4k and
               therefore the calculated partition start does not
               match. For device mapper targets the zipl-helper script
               is used that adjusts the partition start correctly to
               the physical blocksize.
Solution:      Adjust the partition start depending on the physical
               blocksize. 
Reproduction:  Use zipl to install a bootloader on a SCSI disk with 4k
               physical blocksize and without usage of a device mapper
               target. 
Upstream-ID:   4a3957fab5696cc410c5b495956859a424e3552a
Problem-ID:    191696

Upstream-Description:

              zipl: fix reading 4k disk's geometry

              On 4k SCSI disks zipl stores wrong values to 'scsi_mbr.program_table_pointer',
              which makes system unbootable.
              This happens in 'zipl/src/disk.c:656':

              ```
              /* Convert file system block to physical */
              *physical = mapped * phy_per_fs + subblock;
              /* Add partition start */
              *physical += info->geo.start;

              ```

              So 'hd_geometry.start' should be adjusted before being used.

              Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1918723
              Closes: https://github.com/ibm-s390-linux/s390-tools/pull/107
              Signed-off-by: Nikita Dubrovskii <nikita@linux.ibm.com>
              Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
              Signed-off-by: Jan Hoeppner <hoeppner@linux.ibm.com>


Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
---
 zipl/src/disk.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/zipl/src/disk.c
+++ b/zipl/src/disk.c
@@ -444,6 +444,9 @@ type_determined:
 	}
 	/* Convert device size to size in physical blocks */
 	data->phy_blocks = devsize / (data->phy_block_size / 512);
+	/* Adjust start on SCSI according to block_size. device-mapper devices are skipped */
+	if (data->type == disk_type_scsi && target->targetbase == NULL)
+		data->geo.start = data->geo.start / (data->phy_block_size / 512);
 	if (data->partnum != 0)
 		data->partition = stats.st_rdev;
 	/* Try to get device name */