From: "tip-bot2 for Peter Zijlstra" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>,
Josh Poimboeuf <jpoimboe@redhat.com>,
Nick Desaulniers <ndesaulniers@google.com>,
x86@kernel.org, linux-kernel@vger.kernel.org
Subject: [tip: objtool/core] objtool,x86: Rewrite ADD/SUB/AND
Date: Wed, 03 Mar 2021 08:45:33 -0000 [thread overview]
Message-ID: <161476113312.20312.6376931770918404958.tip-bot2@tip-bot2> (raw)
In-Reply-To: <20210211173627.588366777@infradead.org>
The following commit has been merged into the objtool/core branch of tip:
Commit-ID: e1bba6c8930b56c4afe88aa875f3d20d1cef4fe1
Gitweb: https://git.kernel.org/tip/e1bba6c8930b56c4afe88aa875f3d20d1cef4fe1
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Wed, 10 Feb 2021 14:11:30 +01:00
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Wed, 03 Mar 2021 09:38:31 +01:00
objtool,x86: Rewrite ADD/SUB/AND
Support sign extending and imm8 forms.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lkml.kernel.org/r/20210211173627.588366777@infradead.org
---
tools/objtool/arch/x86/decode.c | 70 +++++++++++++++++++++++---------
1 file changed, 51 insertions(+), 19 deletions(-)
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 78ae5be..b42e5ec 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -98,13 +98,14 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
struct list_head *ops_list)
{
struct insn insn;
- int x86_64, sign;
+ int x86_64;
unsigned char op1, op2,
rex = 0, rex_b = 0, rex_r = 0, rex_w = 0, rex_x = 0,
modrm = 0, modrm_mod = 0, modrm_rm = 0, modrm_reg = 0,
sib = 0, /* sib_scale = 0, */ sib_index = 0, sib_base = 0;
struct stack_op *op = NULL;
struct symbol *sym;
+ u64 imm;
x86_64 = is_x86_64(elf);
if (x86_64 == -1)
@@ -200,12 +201,54 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
*type = INSN_JUMP_CONDITIONAL;
break;
- case 0x81:
- case 0x83:
- if (rex != 0x48)
+ case 0x80 ... 0x83:
+ /*
+ * 1000 00sw : mod OP r/m : immediate
+ *
+ * s - sign extend immediate
+ * w - imm8 / imm32
+ *
+ * OP: 000 ADD 100 AND
+ * 001 OR 101 SUB
+ * 010 ADC 110 XOR
+ * 011 SBB 111 CMP
+ */
+
+ /* 64bit only */
+ if (!rex_w)
break;
- if (modrm == 0xe4) {
+ /* %rsp target only */
+ if (!(modrm_mod == 3 && modrm_rm == CFI_SP))
+ break;
+
+ imm = insn.immediate.value;
+ if (op1 & 2) { /* sign extend */
+ if (op1 & 1) { /* imm32 */
+ imm <<= 32;
+ imm = (s64)imm >> 32;
+ } else { /* imm8 */
+ imm <<= 56;
+ imm = (s64)imm >> 56;
+ }
+ }
+
+ switch (modrm_reg & 7) {
+ case 5:
+ imm = -imm;
+ /* fallthrough */
+ case 0:
+ /* add/sub imm, %rsp */
+ ADD_OP(op) {
+ op->src.type = OP_SRC_ADD;
+ op->src.reg = CFI_SP;
+ op->src.offset = imm;
+ op->dest.type = OP_DEST_REG;
+ op->dest.reg = CFI_SP;
+ }
+ break;
+
+ case 4:
/* and imm, %rsp */
ADD_OP(op) {
op->src.type = OP_SRC_AND;
@@ -215,23 +258,12 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec,
op->dest.reg = CFI_SP;
}
break;
- }
- if (modrm == 0xc4)
- sign = 1;
- else if (modrm == 0xec)
- sign = -1;
- else
+ default:
+ /* WARN ? */
break;
-
- /* add/sub imm, %rsp */
- ADD_OP(op) {
- op->src.type = OP_SRC_ADD;
- op->src.reg = CFI_SP;
- op->src.offset = insn.immediate.value * sign;
- op->dest.type = OP_DEST_REG;
- op->dest.reg = CFI_SP;
}
+
break;
case 0x89:
next prev parent reply other threads:[~2021-03-03 14:35 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-11 17:30 [RFC][PATCH v2 0/7] objtool x86 decoder fixes Peter Zijlstra
2021-02-11 17:30 ` [RFC][PATCH v2 1/7] objtool: Allow UNWIND_HINT to suppress dodgy stack modifications Peter Zijlstra
2021-03-03 8:45 ` [tip: objtool/core] " tip-bot2 for Peter Zijlstra
2021-03-06 11:48 ` tip-bot2 for Peter Zijlstra
2021-02-11 17:30 ` [RFC][PATCH v2 2/7] objtool,x86: Renumber CFI_reg Peter Zijlstra
2021-03-03 8:45 ` [tip: objtool/core] " tip-bot2 for Peter Zijlstra
2021-03-06 11:48 ` tip-bot2 for Peter Zijlstra
2021-02-11 17:30 ` [RFC][PATCH v2 3/7] objtool,x86: Rewrite LEA decode Peter Zijlstra
2021-03-03 8:45 ` [tip: objtool/core] " tip-bot2 for Peter Zijlstra
2021-03-06 11:48 ` tip-bot2 for Peter Zijlstra
2021-02-11 17:30 ` [RFC][PATCH v2 4/7] objtool,x86: Rewrite LEAVE Peter Zijlstra
2021-03-03 8:45 ` [tip: objtool/core] " tip-bot2 for Peter Zijlstra
2021-03-06 11:48 ` tip-bot2 for Peter Zijlstra
2021-02-11 17:30 ` [RFC][PATCH v2 5/7] objtool,x86: Simplify register decode Peter Zijlstra
2021-03-03 8:45 ` [tip: objtool/core] " tip-bot2 for Peter Zijlstra
2021-03-06 11:48 ` tip-bot2 for Peter Zijlstra
2021-02-11 17:30 ` [RFC][PATCH v2 6/7] objtool,x86: Support %riz encodings Peter Zijlstra
2021-03-03 8:45 ` [tip: objtool/core] " tip-bot2 for Peter Zijlstra
2021-03-06 11:48 ` tip-bot2 for Peter Zijlstra
2021-02-11 17:30 ` [RFC][PATCH v2 7/7] objtool,x86: Rewrite ADD/SUB/AND Peter Zijlstra
2021-03-03 8:45 ` tip-bot2 for Peter Zijlstra [this message]
2021-03-06 11:48 ` [tip: objtool/core] " tip-bot2 for Peter Zijlstra
2021-02-11 18:30 ` [RFC][PATCH v2 0/7] objtool x86 decoder fixes Nick Desaulniers
2021-02-11 20:17 ` Josh Poimboeuf
2021-02-12 8:53 ` [RFC][PATCH v2 8/7] objtool,x86: More ModRM sugar Peter Zijlstra
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=161476113312.20312.6376931770918404958.tip-bot2@tip-bot2 \
--to=tip-bot2@linutronix.de \
--cc=jpoimboe@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=ndesaulniers@google.com \
--cc=peterz@infradead.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).