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| author | Borislav Petkov <bp@suse.de> | 2020-11-14 06:16:26 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2020-11-14 06:20:33 -0800 |
| commit | 0fa0fc8539f4451bd1ed76867ba87a335e28ff31 (patch) | |
| tree | c010ef4ef967a84d7726f9d1b7f6231350e1e22c /ld | |
| parent | e8b2f0d952184fac8a230db181a4b9810729cd7b (diff) | |
| download | gdb-0fa0fc8539f4451bd1ed76867ba87a335e28ff31.zip gdb-0fa0fc8539f4451bd1ed76867ba87a335e28ff31.tar.gz gdb-0fa0fc8539f4451bd1ed76867ba87a335e28ff31.tar.bz2 | |
x86: Ignore CS/DS/ES/SS segment-override prefixes in 64-bit mode
"In 64-bit mode, the CS, DS, ES, and SS segment-override prefixes have
no effect. These four prefixes are not treated as segment-override
prefixes for the purposes of multiple-prefix rules. Instead, they are
treated as null prefixes." (AMD APM v2).
However, objdump disassembles instructions containing those ignored
prefixes by still generating that segment override:
66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1)
00 00 00 00
Print those segment override prefixes as excessive ones:
66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1)
00 00 00 00
which is what they actually are - they have no effect and the decoding
hardware ignores them.
gas/
2020-11-14 Borislav Petkov <bp@suse.de>
* testsuite/gas/i386/x86-64-segovr.d: Adjust regexes.
* testsuite/gas/i386/x86-64-nops.d: Likewise.
* testsuite/gas/i386/x86-64-nops-1.d: Likewise.
* testsuite/gas/i386/x86-64-nops-1-g64.d: Likewise.
* testsuite/gas/i386/x86-64-nops-1-core2.d: Likewise.
* testsuite/gas/i386/x86-64-nops-1-k8.d: Likewise.
* testsuite/gas/i386/x86-64-nops-2.d: Likewise.
* testsuite/gas/i386/x86-64-nops-3.d: Likewise.
* testsuite/gas/i386/x86-64-nops-4.d: Likewise.
* testsuite/gas/i386/x86-64-nops-4-core2.d: Likewise.
* testsuite/gas/i386/x86-64-nops-4-k8.d: Likewise.
* testsuite/gas/i386/x86-64-nops-5.d: Likewise.
* testsuite/gas/i386/x86-64-nops-5-k8.d: Likewise.
* testsuite/gas/i386/x86-64-nops-7.d: Likewise.
* testsuite/gas/i386/x86-64-nop-1.d: Likewise.
* testsuite/gas/i386/x86-64-align-branch-1a.d: Likewise.
* testsuite/gas/i386/x86-64-align-branch-1b.d: Likewise.
* testsuite/gas/i386/x86-64-align-branch-1c.d: Likewise.
* testsuite/gas/i386/x86-64-align-branch-1d.d: Likewise.
* testsuite/gas/i386/x86-64-align-branch-1g.d: Likewise.
* testsuite/gas/i386/x86-64-align-branch-2c.d: Likewise.
* testsuite/gas/i386/x86-64-align-branch-6.d: Likewise.
* testsuite/gas/i386/x86-64-align-branch-7.d: Likewise.
* testsuite/gas/i386/x86-64-align-branch-8.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-1-core2.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-1-k8.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-1.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-2.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-3.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-4-core2.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-4-k8.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-4.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-5-k8.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops-5.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-nops.d:: Likewise.
ld/
2020-11-14 Borislav Petkov <bp@suse.de>
* testsuite/ld-x86-64/pe-x86-64-4.od: Adjust regexes.
* testsuite/ld-x86-64/tlsld3.dd: Likewise.
* testsuite/ld-x86-64/tlsld4.dd: Likewise.
opcodes/
2020-11-14 Borislav Petkov <bp@suse.de>
* i386-dis.c (ckprefix): Do not assign active_seg_prefix in
64-bit addressing mode.
(NOTRACK_Fixup): Test prefixes for PREFIX_DS, instead of
active_seg_prefix.
Diffstat (limited to 'ld')
| -rw-r--r-- | ld/ChangeLog | 6 | ||||
| -rw-r--r-- | ld/testsuite/ld-x86-64/align-branch-1.d | 2 | ||||
| -rw-r--r-- | ld/testsuite/ld-x86-64/pe-x86-64-4.od | 2 | ||||
| -rw-r--r-- | ld/testsuite/ld-x86-64/tlsld3.dd | 2 | ||||
| -rw-r--r-- | ld/testsuite/ld-x86-64/tlsld4.dd | 2 |
5 files changed, 10 insertions, 4 deletions
diff --git a/ld/ChangeLog b/ld/ChangeLog index 70ea14b..2ae5b487 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,9 @@ +2020-11-14 Borislav Petkov <bp@suse.de> + + * testsuite/ld-x86-64/pe-x86-64-4.od: Adjust regexes. + * testsuite/ld-x86-64/tlsld3.dd: Likewise. + * testsuite/ld-x86-64/tlsld4.dd: Likewise. + 2020-11-13 H.J. Lu <hongjiu.lu@intel.com> PR ld/26869 diff --git a/ld/testsuite/ld-x86-64/align-branch-1.d b/ld/testsuite/ld-x86-64/align-branch-1.d index 19ac6a8..b517365 100644 --- a/ld/testsuite/ld-x86-64/align-branch-1.d +++ b/ld/testsuite/ld-x86-64/align-branch-1.d @@ -13,7 +13,7 @@ Disassembly of section .text: +[a-f0-9]+: 48 85 ff test %rdi,%rdi +[a-f0-9]+: 74 1c je [a-f0-9]+ <_start\+0x25> +[a-f0-9]+: 66 66 66 64 48 8b 04 25 00 00 00 00 data16 data16 data16 mov %fs:0x0,%rax - +[a-f0-9]+: 2e 2e 2e 2e 48 8b 98 fc ff ff ff cs cs cs mov %cs:-0x4\(%rax\),%rbx + +[a-f0-9]+: 2e 2e 2e 2e 48 8b 98 fc ff ff ff cs cs cs cs mov -0x4\(%rax\),%rbx +[a-f0-9]+: 48 85 db test %rbx,%rbx +[a-f0-9]+: 74 00 je [a-f0-9]+ <_start\+0x25> +[a-f0-9]+: c3 ret * diff --git a/ld/testsuite/ld-x86-64/pe-x86-64-4.od b/ld/testsuite/ld-x86-64/pe-x86-64-4.od index e8940ba..302a345 100644 --- a/ld/testsuite/ld-x86-64/pe-x86-64-4.od +++ b/ld/testsuite/ld-x86-64/pe-x86-64-4.od @@ -39,7 +39,7 @@ Disassembly of section .text\$mn: +[a-f0-9]+: 83 c8 ff or \$0xffffffff,%eax +[a-f0-9]+: c7 05 cb 1f 00 00 55 55 44 44 movl \$0x44445555,0x1fcb\(%rip\) # 40301c <Struct\+0x4> +[a-f0-9]+: c3 ret - +[a-f0-9]+: 66 2e 0f 1f 84 00 00 00 00 00 nopw %cs:0x0\(%rax,%rax,1\) + +[a-f0-9]+: 66 2e 0f 1f 84 00 00 00 00 00 cs nopw 0x0\(%rax,%rax,1\) +[a-f0-9]+: 0f 1f 40 00 nopl 0x0\(%rax\) 0+401060 <opti_Od>: diff --git a/ld/testsuite/ld-x86-64/tlsld3.dd b/ld/testsuite/ld-x86-64/tlsld3.dd index 75ac2bf..25310b0 100644 --- a/ld/testsuite/ld-x86-64/tlsld3.dd +++ b/ld/testsuite/ld-x86-64/tlsld3.dd @@ -14,7 +14,7 @@ Disassembly of section .text: [ ]*[a-f0-9]+: 53 push %rbx [ ]*[a-f0-9]+: 48 8d 1d ed ff ff ff lea -0x13\(%rip\),%rbx # [0-9a-f]+ <_start> [ ]*[a-f0-9]+: 4c 01 db add %r11,%rbx -[ ]*[a-f0-9]+: 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 data16 data16 data16 nopw %cs:0x0\(%rax,%rax,1\) +[ ]*[a-f0-9]+: 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 data16 data16 data16 cs nopw 0x0\(%rax,%rax,1\) [ ]*[a-f0-9]+: 64 48 8b 04 25 00 00 00 00 mov %fs:0x0,%rax [ ]*[a-f0-9]+: 8b 80 fc ff ff ff mov -0x4\(%rax\),%eax [ ]*[a-f0-9]+: 5b pop %rbx diff --git a/ld/testsuite/ld-x86-64/tlsld4.dd b/ld/testsuite/ld-x86-64/tlsld4.dd index 711f507..bf5602e 100644 --- a/ld/testsuite/ld-x86-64/tlsld4.dd +++ b/ld/testsuite/ld-x86-64/tlsld4.dd @@ -14,7 +14,7 @@ Disassembly of section .text: [ ]*[a-f0-9]+: 41 57 push %r15 [ ]*[a-f0-9]+: 4c 8d 3d eb ff ff ff lea -0x15\(%rip\),%r15 # [0-9a-f]+ <_start> [ ]*[a-f0-9]+: 4d 01 df add %r11,%r15 -[ ]*[a-f0-9]+: 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 data16 data16 data16 nopw %cs:0x0\(%rax,%rax,1\) +[ ]*[a-f0-9]+: 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 data16 data16 data16 cs nopw 0x0\(%rax,%rax,1\) [ ]*[a-f0-9]+: 64 48 8b 04 25 00 00 00 00 mov %fs:0x0,%rax [ ]*[a-f0-9]+: 8b 80 fc ff ff ff mov -0x4\(%rax\),%eax [ ]*[a-f0-9]+: 41 5f pop %r15 |