Our linker script for optionroms specifies only the placement of the
.text section, leaving the linker free to place the remaining sections
at arbitrary places in the file.
Since at least binutils 2.39, the .note.gnu.build-id section is now
being placed at the start of the file, which causes label addresses to
be shifted. For linuxboot_dma.bin that means that the PnP header
(among others) will not be found when determining the type of ROM at
optionrom_setup():
(0x1c is the label _pnph, where the magic "PnP" is)
$ xxd /usr/share/qemu/linuxboot_dma.bin | grep "PnP"
00000010: 0000 0000 0000 0000 0000 1c00 2450 6e50 ............$PnP
$ xxd pc-bios/optionrom/linuxboot_dma.bin | grep "PnP"
00000010: 0000 0000 0000 0000 0000 4c00 2450 6e50 ............$PnP
^bad
Using a freshly built linuxboot_dma.bin ROM results in a broken boot:
SeaBIOS (version rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org)
Booting from Hard Disk...
Boot failed: could not read the boot disk
Booting from Floppy...
Boot failed: could not read the boot disk
No bootable device.
We're not using the build-id section, so pass the --build-id=none
option to the linker to remove it entirely.
Note: In theory, this same issue could happen with any other
section. The ideal solution would be to have all unused sections
discarded in the linker script. However that would be a larger change,
specially for the pvh rom which uses the .bss and COMMON sections so
I'm addressing only the immediate issue here.
Reported-by: Vasiliy Ulyanov <vulyanov@suse.de>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20230926192502.15986-1-farosas@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In preparation for adding Docker container support, detect compiler options
just once rather than once per Make run; container startup overhead is
substantial and doing the detection just once makes things faster.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220929114231.583801-14-alex.bennee@linaro.org>
Just use using the compiler binary, with -nostdlib in the case of the
linker; the compiler driver (whether i686-*-gcc, or x86_64-*-gcc with
the -m32 option) will then pick the right magic option to as and ld.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The optionrom build is disregarding the flags passed to the configure
script via --cross-cflags-i386. Pass it down and add it to the Makefile.
This will make it possible to get the -m32 flag from $target_cflags to
force a 32-bit build on 64-bit hosts, instead of supplying manually the
arcane -Wa,-32 and linker emulation options.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Do not rely on the detection that was done in the configure script,
since in the future we may want to cross-compile this file.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a new option rom for the multiboot loader, using DMA transfers to copy
data instead of "rep insb".
This significantly lowers QEMU's startup latency by a factor of about 40,
for example, going from 30sec to 0.8sec when loading modules of 120MB
in size.
Signed-off-by: Marcus Hähnel <marcus.haehnel@kernkonzept.com>
Signed-off-by: Adam Lackorzynski <adam@l4re.org>
[Modified to keep the non-DMA code depending on #ifdef USE_FW_CFG_DMA;
do not write below stack. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Recent binutils changes dropping unsupported options [1] caused a build
issue in regard to the optionroms.
ld -m elf_i386 -T /<<PKGBUILDDIR>>/pc-bios/optionrom//flat.lds -no-pie \
-s -o multiboot.img multiboot.o
ld.bfd: Error: unable to disambiguate: -no-pie (did you mean --no-pie ?)
This isn't really a regression in ld.bfd, filing the bug upstream
revealed that this never worked as a ld flag [2] - in fact it seems we
were by accident setting --nmagic).
Since it never had the wanted effect this usage of LDFLAGS_NOPIE, should be
droppable without any effect. This also is the only use-case of LDFLAGS_NOPIE
in .mak, therefore we can also remove it from being added there.
[1]: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=983d925d
[2]: https://sourceware.org/bugzilla/show_bug.cgi?id=27050#c5
Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Message-Id: <20201214150938.1297512-1-christian.ehrhardt@canonical.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
Make it independent from the rules.mak, and clean up to use pattern rules.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Right now the PVH option rom scans for the RSDP from 0xE0000 to
0xE1FFF. This is probobly a typo, it should scan from 0xE0000 to
0xFFFFF.
This is actually an issue on some QEMU versions/machines. For example,
when I run QEMU the RSDP is placed at 0xf5ad0 which will not be picked
up by the current implementation.
This bug still allows a Linux guest to boot (in most configurations) as
the kernel will just scan for the RSDP if one isn't provided.
Signed-off-by: Joe Richey <joerichey@google.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Fixes: 2785dc7b17 ("optionrom: add new PVH option rom")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The new pvh.bin option rom can be used with SeaBIOS to boot
uncompressed kernel using the x86/HVM direct boot ABI.
pvh.S contains the entry point of the option rom. It runs
in real mode, loads the e820 table querying the BIOS, and
then it switches to 32bit protected mode and jumps to the
pvh_load_kernel() written in pvh_main.c.
pvh_load_kernel() loads the cmdline and kernel entry_point
using fw_cfg, then it looks for RSDP, fills the
hvm_start_info required by x86/HVM ABI, and finally jumps
to the kernel entry_point.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
In order to allow other option roms to use these common
useful functions and definitions, this patch put them
in two new C header files called optrom.h and
optrom_fw_cfg.h. We also add useful out*() in*()
functions for different size, and new fw_cfg functions
to use when DMA feature is not available.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
The ROM uses the cmovne instruction, which is new in Pentium Pro and does not
work when running QEMU with "-cpu 486". Avoid producing that instruction.
Suggested-by: Richard W.M. Jones <rjones@redhat.com>
Suggested-by: Thomas Huth <thuth@redhat.com>
Reported-by: Rob Landley <rob@landley.net>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The quiet-command make rule currently takes two arguments:
the command and arguments to run, and a string to print if
the V flag is not set (ie we are not being verbose).
By convention, the string printed is of the form
" NAME some args". Unfortunately to get nicely lined up
output all the strings have to agree about what column the
arguments should start in, which means that if we add a
new quiet-command usage which wants a slightly longer CMD
name then we either put up with misalignment or change
every quiet-command string.
Split the quiet-mode string into two, the "NAME" and
the "same args" part, and use printf(1) to format the
string automatically. This means we only need to change
one place if we want to support a longer maximum name.
In particular, we can now print 7-character names lined
up properly (they are needed for the OSX "SETTOOL" invocation).
Change all the uses of quiet-command to the new syntax.
(Any which are missed or inadvertently reintroduced
via later merges will result in slightly misformatted
quiet output rather than disaster.)
A few places in the pc-bios/ makefiles are updated to use
"BUILD", "SIGN" and "STRIP" rather than "Building",
"Signing" and "Stripping" for consistency and to keep them
below 7 characters. Module .mo links now print "LD" rather
than the nonstandard "LD -r".
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1475598441-27908-1-git-send-email-peter.maydell@linaro.org
