Commit Graph

6 Commits

Author SHA1 Message Date
Mathias Krause 57dc93c967 libpayload: x86/exec - simplify and robustify the code
Simplify the code by directly using the arguments on the stack as base
pointer relative memory references, instead of loading them into
intermediate registers first.

Make it more robust by preserving all callee saved registers mandated by
the C calling convention (and only those), namely EBP, EBX, ESI and EDI.

Don't assume anything about the register state when the called function
returns -- beside the segment registers and the stack pointer to be
still the same as before the call.

Change-Id: I383d6ccefc5b3d5cca37a1c9b638c231bbc48aa8
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Reviewed-on: https://review.coreboot.org/18335
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins)
2017-02-17 17:27:55 +01:00
Mathias Krause 9fa78c136d libpayload: x86/exec - fix argc/argv value passing
According to coreboot’s payload API [1] the argc value should be passed
at stack offset 0x10, so we need to push a dummy value to comply to the
API.

[1] https://www.coreboot.org/Payload_API

Change-Id: Id20424185a5bf7e4d94de1886a2cece3f3968371
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Reviewed-on: https://review.coreboot.org/18333
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2017-02-17 17:24:08 +01:00
Mathias Krause 901efea8ab libpayload: x86/exec - fix return value passing
The pointer to write the return value to is in %ecx, not %eax. Writing
to (%eax) leads to memory corruptions as %eax holds the return value,
e.g. would write zero to address zero for a "successful" returning
payload.

Change-Id: I82df27ae89a9e3d25f479ebdda2b50ea57565459
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Reviewed-on: https://review.coreboot.org/18332
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2017-02-15 21:56:14 +01:00
Mathias Krause d42c38b93c libpayload: x86/exec - fix libpayload API magic value
According to coreboot’s payload API [1] the magic value passed to the
payload should be 0x12345678, not 12345678. Fix that.

[1] https://www.coreboot.org/Payload_API

Change-Id: I10a7f7b1a4aec100416c5e7e4ba7f8add10ef5c5
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Reviewed-on: https://review.coreboot.org/18331
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2017-02-15 21:55:21 +01:00
Elyes HAOUAS 52648623e0 Remove empty lines at end of file
Used command line to remove empty lines at end of file:
find . -type f -exec sed -i -e :a -e '/^\n*$/{$d;N;};/\n$/ba' {} \;

Change-Id: I816ac9666b6dbb7c7e47843672f0d5cc499766a3
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: http://review.coreboot.org/10446
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2015-06-08 00:55:07 +02:00
Stefan Reinauer f6935a006a libpayload: rename i386 to x86
Change-Id: Ia9170bd3d04e76dbf9321ca7ea4be23b5e468d21
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/2033
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
2012-12-14 22:29:17 +01:00
Renamed from payloads/libpayload/arch/i386/exec.S (Browse further)