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5c6808d1a9
The .head.text section contains code that may execute from a different address than it was linked at. This is fragile, given that the x86 ABI can refer to global symbols via absolute or relative references, and the toolchain assumes that these are interchangeable, which they are not in this particular case. For this reason, all absolute symbol references are being removed from code that is emitted into .head.text. Subsequently, build time validation may be added that ensures that no absolute ELF relocations exist at all in that ELF section. In the case of the PVH code, the absolute references are in 32-bit code, which gets emitted with R_X86_64_32 relocations, and these are even more problematic going forward, as it prevents running the linker in PIE mode. So update the 64-bit code to avoid _pa(), and to only rely on relative symbol references: these are always 32-bits wide, even in 64-bit code, and are resolved by the linker at build time. Reviewed-by: Jason Andryuk <jason.andryuk@amd.com> Tested-by: Jason Andryuk <jason.andryuk@amd.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Message-ID: <20241009160438.3884381-12-ardb+git@google.com> Signed-off-by: Juergen Gross <jgross@suse.com> |
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| enlighten.c | ||
| head.S | ||
| Makefile | ||