diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2022-09-15 14:11:29 +0300 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2022-10-17 17:41:15 +0300 |
| commit | bbaceb189a21d7245e8063701fe10985396028f9 (patch) | |
| tree | 45fea6005190ce6561a65e368b18fecd5cf1b9bc /arch/x86/kernel/callthunks.c | |
| parent | 3b6c1747da48ff40ab746b0e860cffe83619f5c5 (diff) | |
| download | linux-bbaceb189a21d7245e8063701fe10985396028f9.tar.xz | |
x86/retbleed: Add SKL call thunk
Add the actual SKL call thunk for call depth accounting.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220915111148.101125588@infradead.org
Diffstat (limited to 'arch/x86/kernel/callthunks.c')
| -rw-r--r-- | arch/x86/kernel/callthunks.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/arch/x86/kernel/callthunks.c b/arch/x86/kernel/callthunks.c index 7b9d998ebd7d..01f6f6b5a93c 100644 --- a/arch/x86/kernel/callthunks.c +++ b/arch/x86/kernel/callthunks.c @@ -7,6 +7,7 @@ #include <linux/moduleloader.h> #include <asm/alternative.h> +#include <asm/asm-offsets.h> #include <asm/cpu.h> #include <asm/ftrace.h> #include <asm/insn.h> @@ -55,7 +56,21 @@ static const struct core_text builtin_coretext = { .name = "builtin", }; -static struct thunk_desc callthunk_desc __ro_after_init; +asm ( + ".pushsection .rodata \n" + ".global skl_call_thunk_template \n" + "skl_call_thunk_template: \n" + __stringify(INCREMENT_CALL_DEPTH)" \n" + ".global skl_call_thunk_tail \n" + "skl_call_thunk_tail: \n" + ".popsection \n" +); + +extern u8 skl_call_thunk_template[]; +extern u8 skl_call_thunk_tail[]; + +#define SKL_TMPL_SIZE \ + ((unsigned int)(skl_call_thunk_tail - skl_call_thunk_template)) extern void error_entry(void); extern void xen_error_entry(void); @@ -157,11 +172,11 @@ static const u8 nops[] = { static __init_or_module void *patch_dest(void *dest, bool direct) { - unsigned int tsize = callthunk_desc.template_size; + unsigned int tsize = SKL_TMPL_SIZE; u8 *pad = dest - tsize; /* Already patched? */ - if (!bcmp(pad, callthunk_desc.template, tsize)) + if (!bcmp(pad, skl_call_thunk_template, tsize)) return pad; /* Ensure there are nops */ @@ -171,9 +186,9 @@ static __init_or_module void *patch_dest(void *dest, bool direct) } if (direct) - memcpy(pad, callthunk_desc.template, tsize); + memcpy(pad, skl_call_thunk_template, tsize); else - text_poke_copy_locked(pad, callthunk_desc.template, tsize, true); + text_poke_copy_locked(pad, skl_call_thunk_template, tsize, true); return pad; } |