From: Thomas Huth <thuth@redhat.com>
To: Cornelia Huck <cohuck@redhat.com>
Cc: "Jason J . Herne" <jjherne@linux.ibm.com>,
Collin Walling <walling@linux.ibm.com>,
Janosch Frank <frankja@linux.ibm.com>,
qemu-devel@nongnu.org,
Christian Borntraeger <borntraeger@de.ibm.com>,
qemu-s390x@nongnu.org, Claudio Imbrenda <imbrenda@linux.ibm.com>
Subject: Re: [PATCH for-5.2 5/6] pc-bios/s390-ccw: Scan through all boot devices if none has been specified
Date: Wed, 5 Aug 2020 11:39:54 +0200 [thread overview]
Message-ID: <706af164-8e74-cba0-df37-55fb9baedb27@redhat.com> (raw)
In-Reply-To: <20200805113633.2822d28d.cohuck@redhat.com>
On 05/08/2020 11.36, Cornelia Huck wrote:
> On Tue, 28 Jul 2020 20:37:33 +0200
> Thomas Huth <thuth@redhat.com> wrote:
>
>> If no boot device has been specified (via "bootindex=..."), the s390-ccw
>> bios scans through all devices to find a bootable device. But so far, it
>> stops at the very first block device (including virtio-scsi controllers
>> without attached devices) that it finds, no matter whether it is bootable
>> or not. That leads to some weird situatation where it is e.g. possible
>> to boot via:
>>
>> qemu-system-s390x -hda /path/to/disk.qcow2
>>
>> but not if there is e.g. a virtio-scsi controller specified before:
>>
>> qemu-system-s390x -device virtio-scsi -hda /path/to/disk.qcow2
>>
>> While using "bootindex=..." is clearly the preferred way of booting
>> on s390x, we still can make the life for the users at least a little
>> bit easier if we look at all available devices to find a bootable one.
>>
>> Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1846975
>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>> ---
>> pc-bios/s390-ccw/main.c | 46 +++++++++++++++++++++++++++--------------
>> 1 file changed, 31 insertions(+), 15 deletions(-)
>
> (...)
>
>> int main(void)
>> {
>> sclp_setup();
>> css_setup();
>> boot_setup();
>> - find_boot_device();
>> - enable_subchannel(blk_schid);
>> - ipl_boot_device();
>> + if (have_iplb) {
>> + find_boot_device();
>> + enable_subchannel(blk_schid);
>> + ipl_boot_device();
>> + } else {
>> + probe_boot_device();
>> + }
>
> The one thing that's a bit surprising with the code is that
> enable_subchannel() sticking out now. The code looking for a boot
> device does that for all subchannels it looks at... but I think
> find_boot_device() did that for specified devices already as well, so
> it seems redundant?
>
> Anyway, that's something that can be looked at later.
Yes, I noticed that, too ... but yes, one clean-up step at a time. I've
put it on my todo-list for later.
>>
>> panic("Failed to load OS from hard disk\n");
>> return 0; /* make compiler happy */
>
> Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Thanks!
Thomas
next prev parent reply other threads:[~2020-08-05 9:40 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-28 18:37 [PATCH for-5.2 0/6] Continue booting in case the first device is not bootable Thomas Huth
2020-07-28 18:37 ` [PATCH for-5.2 1/6] pc-bios/s390-ccw/Makefile: Compile with -std=gnu99, -fwrapv and -fno-common Thomas Huth
2020-07-29 8:00 ` Claudio Imbrenda
2020-07-29 8:34 ` Cornelia Huck
2020-07-31 7:46 ` Janosch Frank
2020-07-31 7:51 ` Thomas Huth
2020-07-28 18:37 ` [PATCH for-5.2 2/6] pc-bios/s390-ccw: Move ipl-related code from main() into a separate function Thomas Huth
2020-07-29 8:01 ` Claudio Imbrenda
2020-07-29 8:47 ` Cornelia Huck
2020-07-29 11:05 ` Thomas Huth
2020-08-05 9:16 ` Cornelia Huck
2020-08-04 12:52 ` Janosch Frank
2020-07-28 18:37 ` [PATCH for-5.2 3/6] pc-bios/s390-ccw: Move the inner logic of find_subch() to " Thomas Huth
2020-07-29 8:54 ` Cornelia Huck
2020-07-29 11:13 ` Thomas Huth
2020-08-05 9:19 ` Cornelia Huck
2020-08-03 8:46 ` Claudio Imbrenda
2020-08-04 13:24 ` Thomas Huth
2020-08-04 15:30 ` Claudio Imbrenda
2020-08-04 13:26 ` Janosch Frank
2020-07-28 18:37 ` [PATCH for-5.2 4/6] pc-bios/s390-ccw: Do not bail out early if not finding a SCSI disk Thomas Huth
2020-07-29 10:03 ` Cornelia Huck
2020-07-28 18:37 ` [PATCH for-5.2 5/6] pc-bios/s390-ccw: Scan through all boot devices if none has been specified Thomas Huth
2020-08-04 11:06 ` Claudio Imbrenda
2020-08-05 9:36 ` Cornelia Huck
2020-08-05 9:39 ` Thomas Huth [this message]
2020-07-28 18:37 ` [PATCH for-5.2 6/6] pc-bios/s390-ccw: Allow booting in case the first virtio-blk disk is bad Thomas Huth
2020-08-05 10:04 ` Cornelia Huck
2020-08-05 10:08 ` Thomas Huth
2020-08-05 10:27 ` Cornelia Huck
2020-07-29 10:10 ` [PATCH for-5.2 0/6] Continue booting in case the first device is not bootable Cornelia Huck
2020-07-29 11:42 ` Viktor Mihajlovski
2020-07-29 17:17 ` Cornelia Huck
2020-07-30 4:39 ` Thomas Huth
2020-08-04 14:49 ` Janosch Frank
2020-08-04 15:19 ` Thomas Huth
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