6867241 fix for 6866143 breaks pxegrub menu load on non-primary NIC

2 files changed, 8 insertions, 7 deletions

diff --git a/usr/src/grub/grub-0.97/stage2/disk_io.c b/usr/src/grub/grub-0.97/stage2/disk_io.c
index bcb37febba..5e767dc747 100644
--- a/usr/src/grub/grub-0.97/stage2/disk_io.c
+++ b/usr/src/grub/grub-0.97/stage2/disk_io.c
@@ -431,15 +431,8 @@ attempt_mount (void)
 {
 #ifndef STAGE1_5
   for (fsys_type = 0; fsys_type < NUM_FSYS; fsys_type++)
-  {
-    /*
-     * (re)set errnum to 0 in order to clear any state that may have
-     * been left from a previous mount (or other) routine.
-     */
-    errnum = 0;
     if ((fsys_table[fsys_type].mount_func) ())
       break;
-  }
 
   if (fsys_type == NUM_FSYS && errnum == ERR_NONE)
     errnum = ERR_FSYS_MOUNT;
diff --git a/usr/src/grub/grub-0.97/stage2/fsys_zfs.c b/usr/src/grub/grub-0.97/stage2/fsys_zfs.c
index 8d5be46475..1d8c99b443 100644
--- a/usr/src/grub/grub-0.97/stage2/fsys_zfs.c
+++ b/usr/src/grub/grub-0.97/stage2/fsys_zfs.c
@@ -1283,6 +1283,7 @@ zfs_mount(void)
 	char tmp_devid[MAXNAMELEN];
 	uint64_t tmp_guid;
 	uint64_t adjpl = (uint64_t)part_length << SPA_MINBLOCKSHIFT;
+	int err = errnum; /* preserve previous errnum state */
 
 	/* if it's our first time here, zero the best uberblock out */
 	if (best_drive == 0 && best_part == 0 && find_best_root) {
@@ -1340,6 +1341,13 @@ zfs_mount(void)
 		}
 	}
 
+	/*
+	 * While some fs impls. (tftp) rely on setting and keeping
+	 * global errnums set, others won't reset it and will break
+	 * when issuing rawreads. The goal here is to simply not
+	 * have zfs mount attempts impact the previous state.
+	 */
+	errnum = err;
 	return (0);
 }