Messages in this thread | | | Date | Fri, 22 May 2020 14:26:15 -0500 | From | Josh Poimboeuf <> | Subject | Re: [patch V6 19/37] x86/irq: Convey vector as argument and not in ptregs |
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On Fri, May 22, 2020 at 02:48:53PM -0400, Boris Ostrovsky wrote: > > Yes. They just make objtool very unhappy: > > > > arch/x86/entry/entry_64.o: warning: objtool: .entry.text+0xfd0: special: > > can't find orig instruction > > > > Peter suggested to use: > > > > .pos = . > > .byte.. > > jmp > > .nops (pos + 8) - . > > > Unfortunately this (.nops directive) only works for newer assemblers > (2.31, per > https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=blob_plain;f=gas/NEWS;h=9a3f352108e439754688e19e63a6235b38801182;hb=5eb617a71463fa6810cd14f57adfe7a1efc93a96) > > > I have 2.27 and things don't go well.
A single nop should be fine, since gas will complain if it tries to move the IP backwards. (Also I'd vote for normal indentation instead of the "assembler magic at 4 spaces" thing.)
.align 8 SYM_CODE_START(irq_entries_start) vector = FIRST_EXTERNAL_VECTOR .rept (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR) pos = . UNWIND_HINT_IRET_REGS .byte 0x6a, vector jmp asm_common_interrupt nop . = pos + 8 vector = vector + 1 .endr SYM_CODE_END(irq_entries_start)
-- Josh
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