Commit Graph

194 Commits

Author SHA1 Message Date
Thomas Huth
a5b2afd522 pc-bios/s390-ccw: Allow building with Clang, too
Clang unfortunately does not support generating code for the z900
architecture level and starts with the z10 instead. Thus to be able
to support compiling with Clang, we have to check for the supported
compiler flags. The disadvantage is of course that the bios image
will only run with z10 guest CPUs upwards (which is what most people
use anyway), so just in case let's also emit a warning in that case
(we will continue to ship firmware images that have been pre-built
with GCC in future releases, so this should not impact normal users,
too).

Message-Id: <20210502174836.838816-5-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-09 18:50:01 +02:00
Philippe Mathieu-Daudé
da231910d3 pc-bios/s390-ccw: Silence GCC 11 stringop-overflow warning
When building on Fedora 34 (gcc version 11.0.0 20210210) we get:

  In file included from pc-bios/s390-ccw/main.c:11:
  In function ‘memset’,
      inlined from ‘boot_setup’ at pc-bios/s390-ccw/main.c:185:5,
      inlined from ‘main’ at pc-bios/s390-ccw/main.c:288:5:
  pc-bios/s390-ccw/libc.h:28:14: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
     28 |         p[i] = c;
        |         ~~~~~^~~

The offending code is:

  memset((char *)S390EP, 0, 6);

where S390EP is a const address:

  #define S390EP 0x10008

The compiler doesn't know how big that pointed area is, so it assume that
its length is zero. This has been reported as BZ#99578 to GCC:
"gcc-11 -Warray-bounds or -Wstringop-overread warning when accessing a
pointer from integer literal"
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578

As this warning does us more harm than good in the BIOS code (where
lot of direct accesses to low memory are done), silence this warning
for all BIOS objects.

Suggested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210422145911.2513980-1-philmd@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20210502174836.838816-4-thuth@redhat.com>
[thuth: Use the pre-existing cc-option macro instead of adding a new one]
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-09 18:47:54 +02:00
Thomas Huth
3462ff3551 pc-bios/s390-ccw: Fix the cc-option macro in the Makefile
The cc-option macro is not doing what it should - compared with the
original from the rules.mak file that got removed with commit
660f793093 ("Makefile: inline the relevant parts of rules.mak"),
the arguments got changed and thus the macro is rather doubling
the QEMU_CFLAGS than adding the flag that should be tested.

Message-Id: <20210502174836.838816-3-thuth@redhat.com>
Fixes: 22fb2ab096 ("pc-bios/s390-ccw: do not use rules.mak")
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-09 18:46:00 +02:00
Thomas Huth
679196a646 pc-bios/s390-ccw: Silence warning from Clang by marking panic() as noreturn
When compiling the s390-ccw bios with Clang, the compiler emits a warning:

 pc-bios/s390-ccw/main.c:210:5: warning: variable 'found' is used uninitialized
  whenever switch default is taken [-Wsometimes-uninitialized]
     default:
     ^~~~~~~
 pc-bios/s390-ccw/main.c:214:16: note: uninitialized use occurs here
     IPL_assert(found, "Boot device not found\n");
                ^~~~~

It's a false positive, it only happens because Clang is not smart enough
to see that the panic() function in the "default:" case can never return.

Anyway, let's explicitely mark panic() with "noreturn" to shut up the
warning.

Message-Id: <20210502174836.838816-2-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-09 18:19:43 +02:00
Thomas Huth
b460a22087 pc-bios/s390-ccw/netboot: Use "-Wl," prefix to pass parameter to the linker
We are using the compiler to do the linking of the bios files. GCC still
accepts the "-Ttext=..." linker flag directly and is smart enough to
pass it to the linker, but in case we are compiling with Clang, we have
to use the official way with the "-Wl," prefix instead.

Message-Id: <20210423153646.593153-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-09 18:14:31 +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
Thomas Huth
d08a649404 pc-bios/s390-ccw/bootmap: Silence compiler warning from Clang
When compiling the s390-ccw bios with Clang, the compiler complains:

 pc-bios/s390-ccw/bootmap.c:302:9: warning: logical not is only applied
  to the left hand side of this comparison [-Wlogical-not-parentheses]
    if (!mbr->dev_type == DEV_TYPE_ECKD) {
        ^              ~~

The code works (more or less by accident), since dev_type can only be
0 or 1, but it's better of course to use the intended != operator here
instead.

Fixes: 5dc739f343 ("Allow booting in case the first virtio-blk disk is bad")
Message-Id: <20210421163331.358178-1-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-09 18:14:31 +02:00
Marc Hartmayer
a6625d38cc pc-bios/s390-ccw: don't try to read the next block if end of chunk is reached
Don't read the block if a null block number is reached, because this means that
the end of chunk is reached.

Reviewed-by: Collin Walling <walling@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Message-Id: <20210416074736.17409-1-mhartmay@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
Eric Farman
d8e5bbdd0d pc-bios: s390x: Ensure Read IPL memory is clean
If, for example, we boot off a virtio device and chreipl to a vfio-ccw
device, the space at lowcore will be non-zero. We build a Read IPL CCW
at address zero, but it will have leftover PSW data that will conflict
with the Format-0 CCW being generated:

0x0: 00080000 80010000
       ------ Ccw0.cda
              -- Ccw0.chainData
                -- Reserved bits

The data address will be overwritten with the correct value (0x0), but
the apparent data chain bit will cause subsequent memory to be used as
the target of the data store, which may not be where we expect (0x0).

Clear out this space when we boot from DASD, so that we know it exists
exactly as we expect.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20201120160117.59366-2-farman@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-11-23 09:48:44 +01:00
Jason J. Herne
872882e771 s390-bios: Skip writing iplb location to low core for ccw ipl
The architecture states that the iplb location is only written to low
core for list directed ipl and not for traditional ccw ipl. If we don't
skip this then operating systems that load by reading into low core
memory may fail to start.

We should also not write the iplb pointer for network boot as it might
overwrite content that we got via network.

Fixes: 9bfc04f9ef ("pc-bios: s390x: Save iplb location in lowcore")
Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20201030122823.347140-1-borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-11-04 12:31:24 +01:00
Janosch Frank
25f5adea5a pc-bios: s390x: Go into disabled wait when encountering a PGM exception
Let's setup a PGM PSW, so we won't load 0s when a program exception
happens. Instead we'll load a disabled wait PSW.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20201006094249.50640-5-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 20:14:48 +02:00
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
4906a4e41c pc-bios: s390x: Fix bootmap.c zipl component entry data handling
The two main types of zipl component entries are execute and
load/data. The last member of the component entry struct therefore
denotes either a PSW or an address. Let's make this a bit more clear
by introducing a union and cleaning up the code that uses that struct
member.

The execute type component entries written by zipl contain short PSWs,
not addresses. Let's mask them and only pass the address part to
jump_to_IPL_code(uint64_t address) because it expects an address as
visible by the name of the argument.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20201006094249.50640-2-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:57:35 +02:00
Marc Hartmayer
468184ec90 pc-bios/s390-ccw: break loop if a null block number is reached
Break the loop if `cur_block_nr` is a null block number because this
means that the end of chunk is reached. In this case we will try to
boot the default entry.

Fixes: ba831b2526 ("s390-ccw: read stage2 boot loader data to find menu")
Reviewed-by: Collin Walling <walling@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Message-Id: <20200924085926.21709-3-mhartmay@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:57:34 +02:00
Marc Hartmayer
5f97ba0c74 pc-bios/s390-ccw: fix off-by-one error
This error takes effect when the magic value "zIPL" is located at the
end of a block. For example if s2_cur_blk = 0x7fe18000 and the magic
value "zIPL" is located at 0x7fe18ffc - 0x7fe18fff.

Fixes: ba831b2526 ("s390-ccw: read stage2 boot loader data to find menu")
Reviewed-by: Collin Walling <walling@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Message-Id: <20200924085926.21709-2-mhartmay@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[thuth: Use "<= ... - 4" instead of "< ... - 3"]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:56:56 +02:00
Thomas Huth
49d4388ec0 pc-bios/s390-ccw/main: Remove superfluous call to enable_subchannel()
enable_subchannel() is already done during is_dev_possibly_bootable()
(which is called from find_boot_device() -> find_subch()), so there
is no need to do this again in the main() function.

Message-Id: <20200806105349.632-9-thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:36:50 +02:00
Thomas Huth
5dc739f343 pc-bios/s390-ccw: Allow booting in case the first virtio-blk disk is bad
If you try to boot with two virtio-blk disks (without bootindex), and
only the second one is bootable, the s390-ccw bios currently stops at
the first disk and does not continue booting from the second one. This
is annoying - and all other major QEMU firmwares succeed to boot from
the second disk in this case, so we should do the same in the s390-ccw
bios, too.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200806105349.632-8-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:36:50 +02:00
Thomas Huth
869d0e2f59 pc-bios/s390-ccw: Scan through all devices if no boot device specified
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
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200806105349.632-7-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:36:50 +02:00
Thomas Huth
605751b5a5 pc-bios/s390-ccw: Do not bail out early if not finding a SCSI disk
In case the user did not specify a boot device, we want to continue
looking for other devices if there are no valid SCSI disks on a virtio-
scsi controller. As a first step, do not panic in this case and let
the control flow carry the error to the upper functions instead.

Message-Id: <20200806105349.632-6-thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:36:50 +02:00
Thomas Huth
d2cf4af1f4 pc-bios/s390-ccw: Move the inner logic of find_subch() to a separate function
Move the code to a separate function to be able to re-use it from a
different spot later.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-Id: <20200806105349.632-5-thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:36:50 +02:00
Thomas Huth
f3180b0266 pc-bios/s390-ccw: Introduce ENODEV define and remove guards of others
Remove the "#ifndef E..." guards from the defines here - the header
guard S390_CCW_H at the top of the file should avoid double definition,
and if the error code is defined in a different file already, we're in
trouble anyway, then it's better to see the error at compile time instead
of hunting weird behavior during runtime later.
Also define ENODEV - we will use this in a later patch.

Message-Id: <20200806105349.632-4-thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:36:50 +02:00
Thomas Huth
d1f060a8b5 pc-bios/s390-ccw: Move ipl-related code from main() into a separate function
Let's move this part of the code into a separate function to be able
to use it from multiple spots later.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Message-Id: <20200806105349.632-3-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:36:50 +02:00
Thomas Huth
4f6a1eb886 pc-bios/s390-ccw/Makefile: Compile with -std=gnu99, -fwrapv and -fno-common
The main QEMU code is compiled with -std=gnu99, -fwrapv and -fno-common.
We should use the same flags for the s390-ccw bios, too, to avoid that
we get different behavior with different compiler versions that changed
their default settings in the course of time (it happened at least with
-std=... and -fno-common in the past already).

While we're at it, also group the other flags here in a little bit nicer
fashion: Move the two "-m" flags out of the "-f" area and specify them on
a separate line.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Message-Id: <20200806105349.632-2-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-06 19:36:50 +02:00
Paolo Bonzini
49b7d74426 build: fix recurse-all target
The missing "/all" suffix prevents the pc-bios/ parts of the build
from running.

In the meanwhile, -Wall has moved from QEMU_CFLAGS to CFLAGS.  Simplify
everything by not passing down CFLAGS, and add -Wall in the recursive
Makefiles.

Reported-by: Miroslav Rezanina <mrezanin@redhat.com>
Reviewed-by: Miroslav Rezanina <mrezanin@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Fixes: 5e6d1573b4 ("remove Makefile.target", 2020-08-21)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-01 08:51:35 -04:00
Thomas Huth
22fb2ab096 pc-bios/s390-ccw: do not use rules.mak
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21 06:18:23 -04:00
Thomas Huth
1c9f655066 pc-bios/s390-ccw: Generate and include dependency files in the Makefile
The Makefile of the s390-ccw bios does not handle dependencies of the
*.c files from the headers yet, so that you often have to run a "make
clean" to get the build right when one of the headers has been changed.
Let's make sure that we generate and include dependency files for all
*.c files now to avoid this problem in the future.

Acked-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200630142955.7662-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 10:00:58 +02:00
Janosch Frank
9598c227aa pc-bios: s390x: Make u32 ptr check explicit
Let's make it a bit more clear that we check the full 64 bits to fit
into the 32 we return.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20200624075226.92728-11-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 10:00:42 +02:00
Janosch Frank
78182aea78 pc-bios: s390x: Use ebcdic2ascii table
Why should we do conversion of a ebcdic value if we have a handy table
where we could look up the ascii value instead?

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: <20200624075226.92728-10-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 10:00:42 +02:00
Janosch Frank
add923b72e pc-bios: s390x: Move panic() into header and add infinite loop
panic() was defined for the ccw and net bios, i.e. twice, so it's
cleaner to rather put it into the header.

Also let's add an infinite loop into the assembly of disabled_wait() so
the caller doesn't need to take care of it.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20200624075226.92728-9-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 10:00:42 +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
b88faa1c89 pc-bios: s390x: Rename PSW_MASK_ZMODE to PSW_MASK_64
This constant enables 64 bit addressing, not the ESAME architecture,
so it shouldn't be named ZMODE.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20200624075226.92728-7-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 10:00:11 +02:00
Janosch Frank
e6d393d097 pc-bios: s390x: Get rid of magic offsets into the lowcore
If we have a lowcore struct that has members for offsets that we want
to touch, why not use it?

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200624075226.92728-5-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 09:59:51 +02:00
Janosch Frank
12ea90dbd8 pc-bios: s390x: Move sleep and yield to helper.h
They are definitely helper functions.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20200624075226.92728-4-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 09:59:51 +02:00
Janosch Frank
e70bc57ba0 pc-bios: s390x: Consolidate timing functions into time.h
Let's consolidate timing related functions into one header.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20200624075226.92728-3-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 09:59:24 +02:00
Janosch Frank
8c6cc7b9df pc-bios: s390x: cio.c cleanup and compile fix
Let's initialize the structs at the beginning to ease reading and also
zeroing all other fields. This also makes the compiler stop
complaining about sense_id_ccw.flags being ored into when it's not
initialized.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200624075226.92728-2-frankja@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-02 09:59:10 +02:00
Philippe Mathieu-Daudé
f7795e4096 misc: Replace zero-length arrays with flexible array member (automatic)
Description copied from Linux kernel commit from Gustavo A. R. Silva
(see [3]):

--v-- description start --v--

  The current codebase makes use of the zero-length array language
  extension to the C90 standard, but the preferred mechanism to
  declare variable-length types such as these ones is a flexible
  array member [1], introduced in C99:

  struct foo {
      int stuff;
      struct boo array[];
  };

  By making use of the mechanism above, we will get a compiler
  warning in case the flexible array does not occur last in the
  structure, which will help us prevent some kind of undefined
  behavior bugs from being unadvertenly introduced [2] to the
  Linux codebase from now on.

--^-- description end --^--

Do the similar housekeeping in the QEMU codebase (which uses
C99 since commit 7be41675f7).

All these instances of code were found with the help of the
following Coccinelle script:

  @@
  identifier s, m, a;
  type t, T;
  @@
   struct s {
      ...
      t m;
  -   T a[0];
  +   T a[];
  };
  @@
  identifier s, m, a;
  type t, T;
  @@
   struct s {
      ...
      t m;
  -   T a[0];
  +   T a[];
   } QEMU_PACKED;

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76497732932f
[3] https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/commit/?id=17642a2fbd2c1

Inspired-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 22:07:42 +01:00
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
Claudio Imbrenda
f24ec9fead pc-bios/s390-ccw: fix sclp_get_loadparm_ascii
The existing s390 bios gets the LOADPARM information from the system using
an SCLP call that specifies a buffer length too small to contain all the
output.

The recent fixes in the SCLP code have exposed this bug, since now the
SCLP call will return an error (as per architecture) instead of
writing partially and completing successfully.

The solution is simply to specify the full page length as the SCCB
length instead of a smaller size.

Fixes: 832be0d8a3 ("s390x: sclp: Report insufficient SCCB length")
Fixes: 9a22473c70 ("pc-bios/s390-ccw: get LOADPARM stored in SCP Read Info")

Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-Id: <1574944437-31182-1-git-send-email-imbrenda@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Tested-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-11-29 09:16:02 +01:00
Yifan Luo
09be82ce53 pc-bios/s390-ccw/net: fix a possible memory leak in get_uuid()
There is a possible memory leak in get_uuid(). Should free allocated mem
before
return NULL.

Signed-off-by: Yifan Luo <luoyifan@cmss.chinamobile.com>
Message-Id: <02cf01d55267$86cf2850$946d78f0$@cmss.chinamobile.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-09-18 17:47:27 +02:00
Thomas Huth
6673ded76c pc-bios/s390-ccw: Do not pre-initialize empty array
Since commit 339686a358 ("pc-bios/s390-ccw:
zero out bss section"), we are clearing now the BSS in start.S, so there
is no need to pre-initialize the loadparm_str array with zeroes anymore.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-09-18 17:47:27 +02:00
Jason J. Herne
2497b4a3c0 s390-bios: Skip bootmap signature entries
Newer versions of zipl have the ability to write signature entries to the boot
script for secure boot. We don't yet support secure boot, but we need to skip
over signature entries while reading the boot script in order to maintain our
ability to boot guest operating systems that have a secure bootloader.

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Message-Id: <1556543381-12671-1-git-send-email-jjherne@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-05-08 10:52:14 +02:00
Markus Armbruster
d796588ba1 pc-bios/s390-ccw: Clean up harmless misuse of isdigit()
atoui() and get_index() pass char values to isdigit().  With a
standard isdigit(), we'd get undefined behavior when the value is
negative.  Can't happen as char is unsigned on s390x.  Even if it
ould, we're actually using isdigit() from pc-bios/s390-ccw/libc.h
here, which works fine for negative values.  Clean up anyway, just
to avoid setting a bad example.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190418145355.21100-6-armbru@redhat.com>
[thuth: updated the commit message]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-05-08 10:52:14 +02:00
Jason J. Herne
2880469c95 s390-bios: Use control unit type to find bootable devices
When the user does not specify which device to boot from then we end
up guessing. Instead of simply grabbing the first available device let's
be a little bit smarter and only choose devices that might be bootable
like disk, and not console devices.

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Message-Id: <1554388475-18329-17-git-send-email-jjherne@linux.ibm.com>
[thuth: Added fix for virtio_is_supported() not being called anymore]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-04-12 12:40:35 +02:00
Jason J. Herne
efa47d36da s390-bios: Support booting from real dasd device
Allows guest to boot from a vfio configured real dasd device.

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <1554388475-18329-16-git-send-email-jjherne@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-04-12 12:40:35 +02:00
Jason J. Herne
69333c36dc s390-bios: Add channel command codes/structs needed for dasd-ipl
The dasd IPL procedure needs to execute a few previously unused
channel commands. Let's define them and their associated data
structures.

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1554388475-18329-15-git-send-email-jjherne@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-04-12 12:40:35 +02:00
Jason J. Herne
3668cb7ce8 s390-bios: Use control unit type to determine boot method
The boot method is different depending on which device type we are
booting from. Let's examine the control unit type to determine if we're
a virtio device. We'll eventually add a case to check for a real dasd device
here as well.

Since we have to call enable_subchannel() in main now, might as well
remove that call from virtio.c : run_ccw(). This requires adding some
additional enable_subchannel calls to not break calls to
virtio_is_supported().

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1554388475-18329-14-git-send-email-jjherne@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-04-12 12:40:35 +02:00
Jason J. Herne
9de6cbb152 s390-bios: Refactor virtio to run channel programs via cio
Now that we have a Channel I/O library let's modify virtio boot code to
make use of it for running channel programs.

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1554388475-18329-13-git-send-email-jjherne@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-04-12 12:40:35 +02:00