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| author | Juergen Gross <jgross@suse.com> | 2021-03-11 15:23:16 +0100 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2021-03-11 19:58:54 +0100 |
| commit | ae755b5a45482b5de4d96d6f35823076af77445e (patch) | |
| tree | b617f4d18ead2e9c92e92f33b6b85086e1747b13 /arch/x86/kernel/paravirt.c | |
| parent | 0b8d366a942fd48a83dfa728e9f8a8d8b20e735f (diff) | |
| download | lwn-ae755b5a45482b5de4d96d6f35823076af77445e.tar.gz lwn-ae755b5a45482b5de4d96d6f35823076af77445e.zip | |
x86/paravirt: Switch iret pvops to ALTERNATIVE
The iret paravirt op is rather special as it is using a jmp instead
of a call instruction. Switch it to ALTERNATIVE.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311142319.4723-12-jgross@suse.com
Diffstat (limited to 'arch/x86/kernel/paravirt.c')
| -rw-r--r-- | arch/x86/kernel/paravirt.c | 26 |
1 files changed, 2 insertions, 24 deletions
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index a688edf35e31..9b0f568b0200 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -86,25 +86,6 @@ u64 notrace _paravirt_ident_64(u64 x) { return x; } - -static unsigned paravirt_patch_jmp(void *insn_buff, const void *target, - unsigned long addr, unsigned len) -{ - struct branch *b = insn_buff; - unsigned long delta = (unsigned long)target - (addr+5); - - if (len < 5) { -#ifdef CONFIG_RETPOLINE - WARN_ONCE(1, "Failing to patch indirect JMP in %ps\n", (void *)addr); -#endif - return len; /* call too long for patch site */ - } - - b->opcode = 0xe9; /* jmp */ - b->delta = delta; - - return 5; -} #endif DEFINE_STATIC_KEY_TRUE(virt_spin_lock_key); @@ -136,9 +117,6 @@ unsigned paravirt_patch_default(u8 type, void *insn_buff, else if (opfunc == _paravirt_ident_64) ret = paravirt_patch_ident_64(insn_buff, len); - else if (type == PARAVIRT_PATCH(cpu.iret)) - /* If operation requires a jmp, then jmp */ - ret = paravirt_patch_jmp(insn_buff, opfunc, addr, len); #endif else /* Otherwise call the function. */ @@ -313,8 +291,6 @@ struct paravirt_patch_template pv_ops = { .cpu.load_sp0 = native_load_sp0, - .cpu.iret = native_iret, - #ifdef CONFIG_X86_IOPL_IOPERM .cpu.invalidate_io_bitmap = native_tss_invalidate_io_bitmap, .cpu.update_io_bitmap = native_tss_update_io_bitmap, @@ -419,6 +395,8 @@ struct paravirt_patch_template pv_ops = { NOKPROBE_SYMBOL(native_get_debugreg); NOKPROBE_SYMBOL(native_set_debugreg); NOKPROBE_SYMBOL(native_load_idt); + +void (*paravirt_iret)(void) = native_iret; #endif EXPORT_SYMBOL(pv_ops); |