| Message ID | 20240712135228.1619332-2-jolsa@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 63ded110979bdd8741542ec66fb9e2d2074aed8c |
| Headers | show |
| Series | uprobe: Fix uretprobe syscall wiring | expand |
On Fri, Jul 12, 2024 at 6:52 AM Jiri Olsa <jolsa@kernel.org> wrote: > > After discussing with Arnd [1] it's preferable to change uretprobe > syscall number to 467 to omit the merge conflict with xattrat syscalls. > > Also changing the ABI to 'common' which will ease up the global > scripts/syscall.tbl management. One consequence is we generate uretprobe > syscall numbers for ABIs that do not support uretprobe syscall, but the > syscall still returns -ENOSYS when called in that ABI. > > [1] https://lore.kernel.org/lkml/784a34e5-4654-44c9-9c07-f9f4ffd952a0@app.fastmail.com/ > > Fixes: 190fec72df4a ("uprobe: Wire up uretprobe system call") > Suggested-by: Arnd Bergmann <arnd@arndb.de> > Signed-off-by: Jiri Olsa <jolsa@kernel.org> > --- > arch/x86/entry/syscalls/syscall_64.tbl | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > sure, why not Acked-by: Andrii Nakryiko <andrii@kernel.org> > diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl > index 6452c2ec469a..dabf1982de6d 100644 > --- a/arch/x86/entry/syscalls/syscall_64.tbl > +++ b/arch/x86/entry/syscalls/syscall_64.tbl > @@ -384,7 +384,7 @@ > 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 > -463 64 uretprobe sys_uretprobe > +467 common uretprobe sys_uretprobe > > # > # Due to a historical design error, certain syscalls are numbered differently > -- > 2.45.2 >
On Fri, Jul 12, 2024 at 03:52:27PM +0200, Jiri Olsa wrote: > After discussing with Arnd [1] it's preferable to change uretprobe > syscall number to 467 to omit the merge conflict with xattrat syscalls. > > Also changing the ABI to 'common' which will ease up the global > scripts/syscall.tbl management. One consequence is we generate uretprobe > syscall numbers for ABIs that do not support uretprobe syscall, but the > syscall still returns -ENOSYS when called in that ABI. > > [1] https://lore.kernel.org/lkml/784a34e5-4654-44c9-9c07-f9f4ffd952a0@app.fastmail.com/ > > Fixes: 190fec72df4a ("uprobe: Wire up uretprobe system call") > Suggested-by: Arnd Bergmann <arnd@arndb.de> > Signed-off-by: Jiri Olsa <jolsa@kernel.org> > --- > arch/x86/entry/syscalls/syscall_64.tbl | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl > index 6452c2ec469a..dabf1982de6d 100644 > --- a/arch/x86/entry/syscalls/syscall_64.tbl > +++ b/arch/x86/entry/syscalls/syscall_64.tbl > @@ -384,7 +384,7 @@ > 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 > -463 64 uretprobe sys_uretprobe > +467 common uretprobe sys_uretprobe > > # > # Due to a historical design error, certain syscalls are numbered differently Isn't include/uapi/asm-generic/unistd.h expected to be updated as well? As of mainline commit v6.10-12246-g786c8248dbd3, it still contains #define __NR_uretprobe 463
On Wed, Jul 24, 2024, at 09:46, Dmitry V. Levin wrote: > On Fri, Jul 12, 2024 at 03:52:27PM +0200, Jiri Olsa wrote: >> diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl >> index 6452c2ec469a..dabf1982de6d 100644 >> --- a/arch/x86/entry/syscalls/syscall_64.tbl >> +++ b/arch/x86/entry/syscalls/syscall_64.tbl >> @@ -384,7 +384,7 @@ >> 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 >> -463 64 uretprobe sys_uretprobe >> +467 common uretprobe sys_uretprobe >> >> # >> # Due to a historical design error, certain syscalls are numbered differently > > Isn't include/uapi/asm-generic/unistd.h expected to be updated as well? > As of mainline commit v6.10-12246-g786c8248dbd3, it still contains > > #define __NR_uretprobe 463 The file is currently unused and replaced with scripts/syscall.tbl, my plan was to remove the old file in the 6.12 syscall cleanups. The number in scripts/syscall.tbl is now 467, so its users (arc, arm64, csky, hegagon, loongarch, nios2 openrisc and riscv) have the same number as on x86. However, the corresponding change did not make it into the other syscall.tbl files (alpha, arm, m68k, microblaze, parisc, powerpc, s390, sh, sparc and xtensa), which is rather inconsistent. I think we should definitely make all non-x86 architectures behave the same way, either with or without an entry for uretprobe. There are three ways do do this: a) remove it from both include/uapi/asm/unistd.h and scripts/syscall.tbl, and change the x86-64 system call to a private number such as 335 b) remove it from both include/uapi/asm/unistd.h and scripts/syscall.tbl, but leave the number at 467 c) add the syscall to all other architectures for consistency, but continue to have it return -ENOSYS. From Linus' earlier comments, I would guess that a) would be the least bad of those. I'm also unsure about the status of the xattrat patches, which were the reason for changing uretprobe from 463 to 467. Those patches are still not merged either, and disappeared from linux-next between Friday and Monday. Arnd
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 6452c2ec469a..dabf1982de6d 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -384,7 +384,7 @@ 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 -463 64 uretprobe sys_uretprobe +467 common uretprobe sys_uretprobe # # Due to a historical design error, certain syscalls are numbered differently
After discussing with Arnd [1] it's preferable to change uretprobe syscall number to 467 to omit the merge conflict with xattrat syscalls. Also changing the ABI to 'common' which will ease up the global scripts/syscall.tbl management. One consequence is we generate uretprobe syscall numbers for ABIs that do not support uretprobe syscall, but the syscall still returns -ENOSYS when called in that ABI. [1] https://lore.kernel.org/lkml/784a34e5-4654-44c9-9c07-f9f4ffd952a0@app.fastmail.com/ Fixes: 190fec72df4a ("uprobe: Wire up uretprobe system call") Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- arch/x86/entry/syscalls/syscall_64.tbl | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)