2024-05-28 14:09:57

by Arnaldo Carvalho de Melo

[permalink] [raw]
Subject: [PATCH 1/1 fyi] tools headers: Update the syscall tables and unistd.h, mostly to support the new 'mseal' syscall

tldr; Just FYI, I'm carrying this on the perf tools tree.

Full explanation:

There used to be no copies, with tools/ code using kernel headers
directly. From time to time tools/perf/ broke due to legitimate kernel
hacking. At some point Linus complained about such direct usage. Then we
adopted the current model.

The way these headers are used in perf are not restricted to just
including them to compile something.

There are sometimes used in scripts that convert defines into string
tables, etc, so some change may break one of these scripts, or new MSRs
may use some different #define pattern, etc.

E.g.:

$ ls -1 tools/perf/trace/beauty/*.sh | head -5
tools/perf/trace/beauty/arch_errno_names.sh
tools/perf/trace/beauty/drm_ioctl.sh
tools/perf/trace/beauty/fadvise.sh
tools/perf/trace/beauty/fsconfig.sh
tools/perf/trace/beauty/fsmount.sh
$
$ tools/perf/trace/beauty/fadvise.sh
static const char *fadvise_advices[] = {
[0] = "NORMAL",
[1] = "RANDOM",
[2] = "SEQUENTIAL",
[3] = "WILLNEED",
[4] = "DONTNEED",
[5] = "NOREUSE",
};
$

The tools/perf/check-headers.sh script, part of the tools/ build
process, points out changes in the original files.

So its important not to touch the copies in tools/ when doing changes in
the original kernel headers, that will be done later, when
check-headers.sh inform about the change to the perf tools hackers.

But also to wire up shadow stacks on 32-bit x86, picking up those
changes from these csets:

ff388fe5c481d39c ("mseal: wire up mseal syscall")
2883f01ec37dd866 ("x86/shstk: Enable shadow stacks for x32")

This makes 'perf trace' support it, now its possible, for instance to
do:

# perf trace -e mseal --max-stack=16

Here is an example with the 'sendmmsg' syscall:

root@x1:~# perf trace -e sendmmsg --max-stack 16 --max-events=1
0.000 ( 0.062 ms): dbus-broker/1012 sendmmsg(fd: 150, mmsg: 0x7ffef57cca50, vlen: 1, flags: DONTWAIT|NOSIGNAL) = 1
syscall_exit_to_user_mode_prepare ([kernel.kallsyms])
syscall_exit_to_user_mode_prepare ([kernel.kallsyms])
syscall_exit_to_user_mode ([kernel.kallsyms])
do_syscall_64 ([kernel.kallsyms])
entry_SYSCALL_64 ([kernel.kallsyms])
[0x117ce7] (/usr/lib64/libc.so.6 (deleted))
root@x1:~#

To do a system wide tracing of the new 'mseal' syscall with a backtrace
of at most 16 entries.

This addresses these perf tools build warnings:

Warning: Kernel ABI header differences:
diff -u tools/include/uapi/asm-generic/unistd.h include/uapi/asm-generic/unistd.h
diff -u tools/perf/arch/x86/entry/syscalls/syscall_64.tbl arch/x86/entry/syscalls/syscall_64.tbl
diff -u tools/perf/arch/powerpc/entry/syscalls/syscall.tbl arch/powerpc/kernel/syscalls/syscall.tbl
diff -u tools/perf/arch/s390/entry/syscalls/syscall.tbl arch/s390/kernel/syscalls/syscall.tbl
diff -u tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl arch/mips/kernel/syscalls/syscall_n64.tbl

Cc: Adrian Hunter <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: H J Lu <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jeff Xu <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: https://lore.kernel.org/lkml/
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/include/uapi/asm-generic/unistd.h | 5 ++++-
tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl | 1 +
tools/perf/arch/powerpc/entry/syscalls/syscall.tbl | 1 +
tools/perf/arch/s390/entry/syscalls/syscall.tbl | 1 +
tools/perf/arch/x86/entry/syscalls/syscall_64.tbl | 3 ++-
5 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/tools/include/uapi/asm-generic/unistd.h b/tools/include/uapi/asm-generic/unistd.h
index 75f00965ab1586cd..d983c48a3b6af175 100644
--- a/tools/include/uapi/asm-generic/unistd.h
+++ b/tools/include/uapi/asm-generic/unistd.h
@@ -842,8 +842,11 @@ __SYSCALL(__NR_lsm_set_self_attr, sys_lsm_set_self_attr)
#define __NR_lsm_list_modules 461
__SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules)

+#define __NR_mseal 462
+__SYSCALL(__NR_mseal, sys_mseal)
+
#undef __NR_syscalls
-#define __NR_syscalls 462
+#define __NR_syscalls 463

/*
* 32 bit systems traditionally used different
diff --git a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
index 532b855df589577b..1464c6be6eb3c752 100644
--- a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
+++ b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
@@ -376,3 +376,4 @@
459 n64 lsm_get_self_attr sys_lsm_get_self_attr
460 n64 lsm_set_self_attr sys_lsm_set_self_attr
461 n64 lsm_list_modules sys_lsm_list_modules
+462 n64 mseal sys_mseal
diff --git a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
index 17173b82ca21dca2..3656f1ca7a21c659 100644
--- a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
@@ -548,3 +548,4 @@
459 common lsm_get_self_attr sys_lsm_get_self_attr
460 common lsm_set_self_attr sys_lsm_set_self_attr
461 common lsm_list_modules sys_lsm_list_modules
+462 common mseal sys_mseal
diff --git a/tools/perf/arch/s390/entry/syscalls/syscall.tbl b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
index 095bb86339a7d378..bd0fee24ad10a3d1 100644
--- a/tools/perf/arch/s390/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
@@ -464,3 +464,4 @@
459 common lsm_get_self_attr sys_lsm_get_self_attr sys_lsm_get_self_attr
460 common lsm_set_self_attr sys_lsm_set_self_attr sys_lsm_set_self_attr
461 common lsm_list_modules sys_lsm_list_modules sys_lsm_list_modules
+462 common mseal sys_mseal sys_mseal
diff --git a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
index 7e8d46f4147f5741..a396f6e6ab5bf97d 100644
--- a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
@@ -374,7 +374,7 @@
450 common set_mempolicy_home_node sys_set_mempolicy_home_node
451 common cachestat sys_cachestat
452 common fchmodat2 sys_fchmodat2
-453 64 map_shadow_stack sys_map_shadow_stack
+453 common map_shadow_stack sys_map_shadow_stack
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
@@ -383,6 +383,7 @@
459 common lsm_get_self_attr sys_lsm_get_self_attr
460 common lsm_set_self_attr sys_lsm_set_self_attr
461 common lsm_list_modules sys_lsm_list_modules
+462 common mseal sys_mseal

#
# Due to a historical design error, certain syscalls are numbered differently
--
2.44.0