Commit Graph

13 Commits

Author SHA1 Message Date
Jared Rossi
f697bed22f pc-bios/s390x: Enable multi-device boot loop
Allow attempts to boot from multiple IPL devices. If the first device fails to
IPL, select the pre-built IPLB for the next device in the boot order and attempt
to IPL from it. Continue this process until IPL is successful or there are no
devices left to try.

Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20241020012953.1380075-18-jrossi@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2024-10-23 06:53:44 +02:00
Jared Rossi
455e3bc3f7 s390x: Rebuild IPLB for SCSI device directly from DIAG308
Because virtio-scsi type devices use a non-architected IPLB pbt code they cannot
be set and stored normally. Instead, the IPLB must be rebuilt during re-ipl.

As s390x does not natively support multiple boot devices, the devno field is
used to store the position in the boot order for the device.

Handling the rebuild as part of DIAG308 removes the need to check the devices
for invalid IPLBs later in the IPL.

Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20241020012953.1380075-17-jrossi@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2024-10-23 06:53:44 +02:00
Jared Rossi
0181e23713 pc-bios/s390-ccw: Enable failed IPL to return after error
Remove panic-on-error from IPL functions such that a return code is propagated
back to the main IPL calling function (rather than terminating immediately),
which facilitates possible error recovery in the future.

A select few panics remain, which indicate fatal non-devices errors that must
result in termination.

Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20241020012953.1380075-13-jrossi@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2024-10-23 06:53:44 +02:00
Jared Rossi
9f4278837d pc-bios/s390-ccw: Use the libc from SLOF and remove sclp prints
We are already using the libc from SLOF for the s390-netboot.img, and
this libc implementation is way more complete and accurate than the
simple implementation that we currently use for the s390-ccw.img binary.
Since we are now always assuming that the SLOF submodule is available
when building the s390-ccw bios (see commit bf6903f694), we can drop
the simple implementation and use the SLOF libc for the s390-ccw.img
binary, too.

Additionally replace sclp_print calls with puts/printf now that it is
available.

Co-authored by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
Message-ID: <20241020012953.1380075-3-jrossi@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2024-10-23 06:53:44 +02:00
Thomas Huth
052b66e721 pc-bios/s390-ccw: Fix inline assembly for older versions of Clang
Clang versions before v11.0 insist on having the %rX or %cX register
names instead of just a number. Since our Travis-CI is currently
still using Clang v6.0, we have to fix this to avoid failing jobs.

Message-Id: <20210512171550.476130-2-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-14 12:38:43 +02:00
Thomas Huth
ff77712a8a pc-bios/s390-ccw: Use reset_psw pointer instead of hard-coded null pointer
When compiling the s390-ccw bios with clang, it emits a warning like this:

 pc-bios/s390-ccw/jump2ipl.c:86:9: warning: indirection of non-volatile null
  pointer will be deleted, not trap [-Wnull-dereference]
     if (*((uint64_t *)0) & RESET_PSW_MASK) {
         ^~~~~~~~~~~~~~~~
 pc-bios/s390-ccw/jump2ipl.c:86:9: note: consider using __builtin_trap() or
  qualifying pointer with 'volatile'

We could add a "volatile" here to shut it up, but on the other hand,
we also have a pointer variable called "reset_psw" in this file already
that points to the PSW at address 0, so we can simply use that pointer
variable instead.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210423142440.582188-1-thuth@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-09 18:14:31 +02:00
Eric Farman
3d6519968b pc-bios: s390x: Clear out leftover S390EP string
A Linux binary will have the string "S390EP" at address 0x10008,
which is important in getting the guest up off the ground. In the
case of a reboot (specifically chreipl going to a new device),
we should defer to the PSW at address zero for the new config,
which will re-write "S390EP" from the new image.

Let's clear it out at this point so that a reipl to, say, a DASD
passthrough device drives the IPL path from scratch without disrupting
disrupting the order of operations for other boots.

Rather than hardcoding the address of this magic (again), let's
define it somewhere so that the two users are visibly related.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20201120160117.59366-3-farman@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-11-23 09:48:45 +01:00
Janosch Frank
42ab98e7d7 pc-bios: s390x: Use reset PSW if avaliable
If a blob provides a reset PSW then we should use it instead of
branching to the PSW address and using our own mask.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20201006094249.50640-4-frankja@linux.ibm.com>
[thuth: Use Elvis operator to shorten long line]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 20:14:17 +02:00
Janosch Frank
26e0b96fa9 pc-bios: s390x: Save PSW rework
We don't need to save the ipl_continue variable in lowcore and have it
limited to 32 bits because of the lowcore layout. Let's move it to a
new 64 bit variable and get rid of the reset info struct.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20201006094249.50640-3-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:57:35 +02:00
Janosch Frank
fe75c657b8 pc-bios: s390x: Use PSW masks where possible and introduce PSW_MASK_SHORT_ADDR
Let's move some of the PSW mask defines into s390-arch.h and use them
in jump2ipl.c. Also let's introduce a new constant for the address
mask of 8 byte (short) PSWs.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20200624075226.92728-8-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 10:00:32 +02:00
Janosch Frank
9bfc04f9ef pc-bios: s390x: Save iplb location in lowcore
The POP states that for a list directed IPL the IPLB is stored into
memory by the machine loader and its address is stored at offset 0x14
of the lowcore.

ZIPL currently uses the address in offset 0x14 to access the IPLB and
acquire flags about secure boot. If the IPLB address points into
memory which has an unsupported mix of flags set, ZIPL will panic
instead of booting the OS.

As the lowcore can have quite a high entropy for a guest that did drop
out of protected mode (i.e. rebooted) we encountered the ZIPL panic
quite often.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Tested-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Message-Id: <20200304114231.23493-19-frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-03-10 10:18:08 +01:00
Janosch Frank
5c6f0d5f46 pc-bios/s390x: Fix reset psw mask
We need to set the short psw indication bit in the reset psw, as it is
a short psw.

Exposed by "s390x: Properly fetch and test the short psw on diag308
subc 0/1".

Fixes: 9629823290 ("pc-bios/s390-ccw: do a subsystem reset before running the guest")
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-Id: <20191203132813.2734-5-frankja@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-12-18 15:54:24 +01:00
Thomas Huth
9a848adf45 pc-bios/s390-ccw/net: Use diag308 to reset machine before jumping to the OS
The netboot firmware so far simply jumped directly into the OS kernel
after the download has been completed. This, however, bears the risk
that the virtio-net device still might be active in the background and
incoming packets are still placed into the buffers - which could destroy
memory of the now-running Linux kernel in case it did not take over the
device fast enough. Also the SCLP console is not put into a well-defined
state here. We should hand over the system in a clean state when jumping
into the kernel, so let's use the same mechanism as it's done in the
main s390-ccw firmware and reset the machine with diag308 into a clean
state before jumping into the OS kernel code. To be able to share the
code with the main s390-ccw firmware, the related functions are now
extracted from bootmap.c into a new file called jump2ipl.c.

Since we now also set the boot device schid at address 184 for the network
boot device, this patch also slightly changes the way how we detect the
entry points for non-ELF binary images: The code now looks for the "S390EP"
magic first and then jumps to 0x10000 in case it has been found. This is
necessary for booting from network devices, since the normal kernel code
(where the PSW at ddress 0 points to) tries to do a block load from the
boot device. This of course fails for a virtio-net device and causes the
kernel to abort with a panic-PSW silently.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2018-05-02 11:27:14 +02:00