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Peter Zijlstra
ba08abca66
Commitab234a260b("x86/pv: Rework arch_local_irq_restore() to not use popf") replaced "push %reg; popf" with something like: "test $0x200, %reg; jz 1f; sti; 1:", which breaks the pushf/popf symmetry that commitea24213d80("objtool: Add UACCESS validation") relies on. The result is: drivers/gpu/drm/amd/amdgpu/si.o: warning: objtool: si_common_hw_init()+0xf36: PUSHF stack exhausted Meanwhile, commitc9c324dc22("objtool: Support stack layout changes in alternatives") makes that we can actually use stack-ops in alternatives, which means we can revert1ff865e343("x86,smap: Fix smap_{save,restore}() alternatives"). That in turn means we can limit the PUSHF/POPF handling ofea24213d80to those instructions that are in alternatives. Fixes:ab234a260b("x86/pv: Rework arch_local_irq_restore() to not use popf") Reported-by: Borislav Petkov <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Josh Poimboeuf <[email protected]> Link: https://lkml.kernel.org/r/[email protected]