From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Robbie Harwood <rharwood@redhat.com>
Date: Wed, 25 Jan 2023 16:10:58 -0500
Subject: [PATCH] ppc64le: signed boot media changes

Skip mdraid < 1.1 on isos since mdraid* can't even

Prior to this change, on ppc64le with part_msdos and the mdraid* modules
enabled, we see:

    disk/diskfilter.c:191: scanning ieee1275/cdrom
    kern/disk.c:196: Opening `ieee1275/cdrom'...
    disk/ieee1275/ofdisk.c:477: Opening `cdrom'.
    disk/ieee1275/ofdisk.c:502: MAX_RETRIES set to 20
    kern/disk.c:288: Opening `ieee1275/cdrom' succeeded.
    disk/diskfilter.c:136: Scanning for DISKFILTER devices on disk ieee1275/cdrom
    partmap/msdos.c:184: partition 0: flag 0x80, type 0x96, start 0x0, len
    0x6a5d70
    disk/diskfilter.c:136: Scanning for DISKFILTER devices on disk ieee1275/cdrom
    SCSI-DISK: Access beyond end of device !
    SCSI-DISK: Access beyond end of device !
    SCSI-DISK: Access beyond end of device !
    SCSI-DISK: Access beyond end of device !
    SCSI-DISK: Access beyond end of device !
    disk/ieee1275/ofdisk.c:578: MAX_RETRIES set to 20

These latter two lines repeat many times, eventually ending in:

    kern/disk.c:388: ieee1275/cdrom read failed
    error: ../../grub-core/disk/ieee1275/ofdisk.c:608:failure reading sector
    0x1a9720 from `ieee1275/cdrom'.

and the system drops to a "grub>" prompt.

Prior to 1.1, mdraid stored the superblock offset from the end of the
disk, and the firmware really doesn't like reads there.  Best guess was
that the firmware and the iso image appear to diagree on the blocksize
(512 vs. 2048), and the diskfilter RAID probing is too much for it.
It's tempting to just skip probing for cdroms, but unfortunately isos
can be virtualized elsewhere - such as regular disks.

Also fix detection of root, and try the chrp path as a fallback if the
built prefix doesn't work.

Signed-off-by: Robbie Harwood <rharwood@redhat.com>

wip
---
 grub-core/disk/mdraid1x_linux.c  | 8 +++++++-
 grub-core/disk/mdraid_linux.c    | 5 +++++
 grub-core/kern/ieee1275/openfw.c | 2 +-
 grub-core/normal/main.c          | 5 +++++
 4 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/grub-core/disk/mdraid1x_linux.c b/grub-core/disk/mdraid1x_linux.c
index 38444b02c7..08c57ae16e 100644
--- a/grub-core/disk/mdraid1x_linux.c
+++ b/grub-core/disk/mdraid1x_linux.c
@@ -129,7 +129,13 @@ grub_mdraid_detect (grub_disk_t disk,
       grub_uint32_t level;
       struct grub_diskfilter_vg *array;
       char *uuid;
-	
+
+#ifdef __powerpc__
+      /* Firmware will yell at us for reading too far. */
+      if (minor_version == 0)
+        continue;
+#endif
+
       if (size == GRUB_DISK_SIZE_UNKNOWN && minor_version == 0)
 	continue;
 	
diff --git a/grub-core/disk/mdraid_linux.c b/grub-core/disk/mdraid_linux.c
index e40216f511..98fcfb1be6 100644
--- a/grub-core/disk/mdraid_linux.c
+++ b/grub-core/disk/mdraid_linux.c
@@ -189,6 +189,11 @@ grub_mdraid_detect (grub_disk_t disk,
   grub_uint32_t level;
   struct grub_diskfilter_vg *ret;
 
+#ifdef __powerpc__
+  /* Firmware will yell at us for reading too far. */
+  return NULL;
+#endif
+
   /* The sector where the mdraid 0.90 superblock is stored, if available.  */
   size = grub_disk_native_sectors (disk);
   if (size == GRUB_DISK_SIZE_UNKNOWN)
diff --git a/grub-core/kern/ieee1275/openfw.c b/grub-core/kern/ieee1275/openfw.c
index 3a6689abb1..0278054c61 100644
--- a/grub-core/kern/ieee1275/openfw.c
+++ b/grub-core/kern/ieee1275/openfw.c
@@ -499,7 +499,7 @@ grub_ieee1275_encode_devname (const char *path)
 	*optr++ ='\\';
       *optr++ = *iptr++;
     }
-  if (partition && partition[0])
+  if (partition && partition[0] >= '0' && partition[0] <= '9')
     {
       unsigned int partno = grub_strtoul (partition, 0, 0);
 
diff --git a/grub-core/normal/main.c b/grub-core/normal/main.c
index 8f5fd81003..d59145f861 100644
--- a/grub-core/normal/main.c
+++ b/grub-core/normal/main.c
@@ -372,6 +372,7 @@ grub_try_normal_prefix (const char *prefix)
            file = grub_file_open (config, GRUB_FILE_TYPE_CONFIG);
            if (file)
              {
+               grub_env_set ("prefix", prefix);
                grub_file_close (file);
                err = GRUB_ERR_NONE;
              }
@@ -447,6 +448,10 @@ grub_cmd_normal (struct grub_command *cmd __attribute__ ((unused)),
       err = grub_try_normal ("fw_path");
       if (err == GRUB_ERR_FILE_NOT_FOUND)
         err = grub_try_normal ("prefix");
+#ifdef __powerpc__
+      if (err == GRUB_ERR_FILE_NOT_FOUND)
+        err = grub_try_normal_prefix ("/boot/grub");
+#endif
       if (err == GRUB_ERR_FILE_NOT_FOUND)
         err = grub_try_normal_discover ();
       if (err == GRUB_ERR_FILE_NOT_FOUND)