tree 8cd2f7e395c72ba80cf422e78fc4ae20a1c72af5
parent e1d0285c89ae5c7d0d3b1fdede92d2cf9d12bb01
author Alexandru Elisei <alexandru.elisei@arm.com> 1589470704 +0100
committer Will Deacon <will@kernel.org> 1589906281 +0100

Don't allow more than one framebuffers

A vesa device is used by the SDL, GTK or VNC framebuffers. Don't allow the
user to specify more than one of these options because kvmtool will create
identical vesa devices and bad things will happen:

$ ./lkvm run -c2 -m2048 -k bzImage --sdl --gtk
  # lkvm run -k bzImage -m 2048 -c 2 --name guest-10159
  Error: device region [d0000000-d012bfff] would overlap device region [d0000000-d012bfff]
*** Error in `./lkvm': free(): invalid pointer: 0x00007fad78002e40 ***
*** Error in `./lkvm': free(): invalid pointer: 0x00007fad78002e40 ***
*** Error in `./lkvm': free(): invalid pointer: 0x00007fad78002e40 ***
======= Backtrace: =========
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x777e5)[0x7fae0ed447e5]
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6/lib/x86_64-linux-gnu/libc.so.6(+0x8037a)[0x7fae0ed4d37a]
(+0x777e5)[0x7fae0ed447e5]
/lib/x86_64-linux-gnu/libc.so.6(+0x777e5)[0x7fae0ed447e5]
/lib/x86_64-linux-gnu/libc.so.6(+0x8037a)[0x7fae0ed4d37a]
/lib/x86_64-linux-gnu/libc.so.6(cfree+0x4c)[0x7fae0ed5153c]
*** Error in `./lkvm': free(): invalid pointer: 0x00007fad78002e40 ***
/lib/x86_64-linux-gnu/libglib-2.0.so.0(g_string_free+0x3b)[0x7fae0f814dab]
/lib/x86_64-linux-gnu/libglib-2.0.so.0(g_string_free+0x3b)[0x7fae0f814dab]
/usr/lib/x86_64-linux-gnu/libgtk-3.so.0(+0x21121c)[0x7fae1023321c]
/usr/lib/x86_64-linux-gnu/libgtk-3.so.0(+0x21121c)[0x7fae1023321c]
======= Backtrace: =========
Aborted (core dumped)

The vesa device is explicitly created during the initialization phase of
the above framebuffers. Also remove the superfluous check for their
existence.

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Link: https://lore.kernel.org/r/1589470709-4104-8-git-send-email-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>