On 18/03/2024 11.30, Kautuk Consul wrote:
While testing with a qcow2 with a DOS boot partition it was found that
when we set the logical_block_size in the guest XML to >512 then the
boot would fail
...
diff --git a/slof/fs/packages/disk-label.fs b/slof/fs/packages/disk-label.fs
index 661c6b0..2630701 100644
--- a/slof/fs/packages/disk-label.fs
+++ b/slof/fs/packages/disk-label.fs
@@ -132,11 +132,16 @@ CONSTANT /gpt-part-entry
debug-disk-label? IF dup ." actual=" .d cr THEN
;
-\ read sector to array "block"
-: read-sector ( sector-number -- )
+\ read sector to array "block" and return actual bytes read
+: read-sector-ret ( sector-number -- actual-bytes )
\ block-size is 0x200 on disks, 0x800 on cdrom drives
block-size * 0 seek drop \ seek to sector
- block block-size read drop \ read sector
+ block block-size read \ read sector
+;
+
+\ read sector to array "block"
+: read-sector ( sector-number -- )
+ read-sector-ret drop
;
: (.part-entry) ( part-entry )
@@ -204,7 +209,8 @@ CONSTANT /gpt-part-entry
part-entry>sector-offset l@-le ( current sector )
dup to part-start to lpart-start ( current )
I just noticed that according to the stack comment above, there is a
"current" item on the stack...
BEGIN
- part-start read-sector \ read EBR
+ part-start read-sector-ret \ read EBR
+ block-size < IF UNLOOP 0 EXIT THEN
... which doesn't get dropped here before the EXIT ? Is the stack still
right after this function exited early?
1 partition>start-sector IF
\ ." Logical Partition found at " part-start .d cr
1+
@@ -279,6 +285,7 @@ CONSTANT /gpt-part-entry
THEN
count-dos-logical-partitions TO dos-logical-partitions
+ dos-logical-partitions 0= IF false EXIT THEN
debug-disk-label? IF
." Found " dos-logical-partitions .d ." logical partitions" cr
@@ -352,6 +359,7 @@ CONSTANT /gpt-part-entry
no-mbr? IF drop FALSE EXIT THEN \ read MBR and check for DOS disk-label magic
count-dos-logical-partitions TO dos-logical-partitions
+ dos-logical-partitions 0= IF 0 EXIT THEN
Similar question here, what about the "addr" stack item? Shouldn't it be
dropped first?
Thomas
PS: I'm still having trouble receiving your mail, I just discovered v2 on
patchwork and downloaded it from there...
