]>
Commit | Line | Data |
---|---|---|
95e114a0 | 1 | /* Restartable Sequences Linux s390 architecture header. |
6d7e8eda | 2 | Copyright (C) 2021-2023 Free Software Foundation, Inc. |
95e114a0 FW |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or | |
5 | modify it under the terms of the GNU Lesser General Public | |
6 | License as published by the Free Software Foundation; either | |
7 | version 2.1 of the License, or (at your option) any later version. | |
8 | ||
9 | The GNU C Library is distributed in the hope that it will be useful, | |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
12 | Lesser General Public License for more details. | |
13 | ||
14 | You should have received a copy of the GNU Lesser General Public | |
15 | License along with the GNU C Library; if not, see | |
16 | <https://www.gnu.org/licenses/>. */ | |
17 | ||
18 | #ifndef _SYS_RSEQ_H | |
19 | # error "Never use <bits/rseq.h> directly; include <sys/rseq.h> instead." | |
20 | #endif | |
21 | ||
22 | /* RSEQ_SIG is a signature required before each abort handler code. | |
23 | ||
24 | It is a 32-bit value that maps to actual architecture code compiled | |
25 | into applications and libraries. It needs to be defined for each | |
26 | architecture. When choosing this value, it needs to be taken into | |
27 | account that generating invalid instructions may have ill effects on | |
28 | tools like objdump, and may also have impact on the CPU speculative | |
29 | execution efficiency in some cases. | |
30 | ||
31 | RSEQ_SIG uses the trap4 instruction. As Linux does not make use of the | |
32 | access-register mode nor the linkage stack this instruction will always | |
33 | cause a special-operation exception (the trap-enabled bit in the DUCT | |
34 | is and will stay 0). The instruction pattern is | |
35 | b2 ff 0f ff trap4 4095(%r0) */ | |
36 | ||
37 | #define RSEQ_SIG 0xB2FF0FFF |