From: Kautuk Consul <kconsul@linux.ibm.com>
To: Segher Boessenkool <segher@kernel.crashing.org>,
aik@ozlabs.ru, Thomas Huth <thuth@redhat.com>
Cc: slof@lists.ozlabs.org, kvm-ppc@vger.kernel.org,
Kautuk Consul <kconsul@linux.ibm.com>
Subject: [PATCH v4] slof/fs/packages/disk-label.fs: improve checking for DOS boot partitions
Date: Thu, 28 Mar 2024 02:00:09 -0400 [thread overview]
Message-ID: <20240328060009.650859-1-kconsul@linux.ibm.com> (raw)
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 in the following interminable loop:
<SNIP>
Trying to load: from: /pci@800000020000000/scsi@3 ...
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
</SNIP>
Change the "read-sector" Forth subroutine to throw an exception whenever
it fails to read a full block-size length of sector from the disk.
Also change the "open" method to initiate CATCH exception handling for the calls to
try-partitions/try-files which will also call read-sector which could potentially
now throw this new exception.
After making the above changes, it fails properly with the correct error
message as follows:
<SNIP>
Trying to load: from: /pci@800000020000000/scsi@3 ...
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
virtioblk_transfer: Access beyond end of device!
E3404: Not a bootable device!
E3407: Load failed
Type 'boot' and press return to continue booting the system.
Type 'reset-all' and press return to reboot the system.
Ready!
0 >
</SNIP>
Signed-off-by: Kautuk Consul <kconsul@linux.ibm.com>
---
slof/fs/packages/disk-label.fs | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/slof/fs/packages/disk-label.fs b/slof/fs/packages/disk-label.fs
index 661c6b0..a6fb231 100644
--- a/slof/fs/packages/disk-label.fs
+++ b/slof/fs/packages/disk-label.fs
@@ -136,7 +136,8 @@ CONSTANT /gpt-part-entry
: read-sector ( sector-number -- )
\ 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
+ block-size < IF throw THEN \ if we read less than the block-size then throw an exception
;
: (.part-entry) ( part-entry )
@@ -723,10 +724,15 @@ CREATE GPT-LINUX-PARTITION 10 allot
THEN
partition IF
- try-partitions
+ ['] try-partitions
ELSE
- try-files
+ ['] try-files
THEN
+
+ \ Catch any exception that might happen due to read-sector failing to read
+ \ block-size number of bytes from any sector of the disk.
+ CATCH IF false THEN
+
dup 0= IF debug-disk-label? IF ." not found." cr THEN close THEN \ free memory again
;
--
2.31.1
next reply other threads:[~2024-03-28 6:00 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-28 6:00 Kautuk Consul [this message]
2024-04-04 0:35 ` [PATCH v4] slof/fs/packages/disk-label.fs: improve checking for DOS boot partitions Alexey Kardashevskiy
2024-04-04 7:18 ` Kautuk Consul
2024-04-05 3:46 ` Alexey Kardashevskiy
2024-04-05 8:16 ` Kautuk Consul
2024-04-16 4:33 ` [SLOF] " Kautuk Consul
2024-04-25 7:14 ` Kautuk Consul
2024-05-03 10:08 ` Kautuk Consul
2024-05-14 9:08 ` Kautuk Consul
2024-05-20 9:03 ` Alexey Kardashevskiy
2024-05-22 8:55 ` Kautuk Consul
2024-05-27 12:38 ` Alexey Kardashevskiy
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