[PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[H.J. Lu]

X32 uses the same 64-bit syscall interface for set_thread_area.  But
__NR_set_thread_area is missing from <asm/unistd_x32.h>.  A kernel patch
was submitted:

From 7b05d5b43ae2545e0d4a3edb24205d18bc883626 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Sat, 15 Aug 2020 10:34:00 -0700
Subject: [PATCH] x86-64: Enable x32 set_thread_area

X32 uses the common 64-bit syscall interface for set_thread_area.  Tested
with tools/testing/selftests/x86/sigreturn.c on x32.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
---
 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 37b844f839bc..670193a73f6e 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -213,7 +213,7 @@
 202	common	futex			sys_futex
 203	common	sched_setaffinity	sys_sched_setaffinity
 204	common	sched_getaffinity	sys_sched_getaffinity
-205	64	set_thread_area
+205	common	set_thread_area
 206	64	io_setup		sys_io_setup
 207	common	io_destroy		sys_io_destroy
 208	common	io_getevents		sys_io_getevents
--
2.26.2

Add <asm/unistd_x32.h> for older kernel header files and regenerate
x32 arch-syscall.h.
---
 sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h | 9 +++++++++
 sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h    | 1 +
 2 files changed, 10 insertions(+)
 create mode 100644 sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h

diff --git a/sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h b/sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h
new file mode 100644
index 0000000000..4de22a7737
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h
@@ -0,0 +1,9 @@
+/* FIXME: __NR_set_thread_area should come from the kernel header file.
+   This file should be removed if <asm/unistd_x32.h> from the kernel
+   header file contains __NR_set_thread_area.  */
+
+#include_next <asm/unistd_x32.h>
+
+#ifndef __NR_set_thread_area
+# define __NR_set_thread_area 1073742029
+#endif
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h b/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
index 1a701c1472..7b64b1fa0c 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
@@ -260,6 +260,7 @@
 #define __NR_sendto 1073741868
 #define __NR_set_mempolicy 1073742062
 #define __NR_set_robust_list 1073742354
+#define __NR_set_thread_area 1073742029
 #define __NR_set_tid_address 1073742042
 #define __NR_setdomainname 1073741995
 #define __NR_setfsgid 1073741947
-- 
2.26.2

Re: [PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[Florian Weimer]

* H. J. Lu via Libc-alpha:

> diff --git a/sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h b/sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h
> new file mode 100644
> index 0000000000..4de22a7737
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h
> @@ -0,0 +1,9 @@
> +/* FIXME: __NR_set_thread_area should come from the kernel header file.
> +   This file should be removed if <asm/unistd_x32.h> from the kernel
> +   header file contains __NR_set_thread_area.  */
> +
> +#include_next <asm/unistd_x32.h>
> +
> +#ifndef __NR_set_thread_area
> +# define __NR_set_thread_area 1073742029
> +#endif

I think you can use sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
for this.  It's more tailored to this purpose.  arc and arm already
use it.

Thanks,
Florian

Re: [PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[H.J. Lu]

On Mon, Aug 24, 2020 at 4:17 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu via Libc-alpha:
>
> > diff --git a/sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h b/sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h
> > new file mode 100644
> > index 0000000000..4de22a7737
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/x86/include/asm/unistd_x32.h
> > @@ -0,0 +1,9 @@
> > +/* FIXME: __NR_set_thread_area should come from the kernel header file.
> > +   This file should be removed if <asm/unistd_x32.h> from the kernel
> > +   header file contains __NR_set_thread_area.  */
> > +
> > +#include_next <asm/unistd_x32.h>
> > +
> > +#ifndef __NR_set_thread_area
> > +# define __NR_set_thread_area 1073742029
> > +#endif
>
> I think you can use sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
> for this.  It's more tailored to this purpose.  arc and arm already
> use it.

It doesn't work in this case.  <fixup-asm-unistd.h> is used to undefine or
redefine a syscall from <asm/unistd.h>.   The actual syscall numbers still
come from <asm/unistd.h>.  In this case, the sycall number is missing from
<asm/unistd_x32.h>.   My patch is a prerequisite for a new testcase:

../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c: In function ‘setup_ldt’:
../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c:258:14: error:
‘SYS_set_thread_area’ undeclared (first use in this function)
  258 |  if (syscall(SYS_set_thread_area, &gdt_data16_desc) == 0) {
      |              ^~~~~~~~~~~~~~~~~~~

-- 
H.J.

Re: [PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[Florian Weimer]

* H. J. Lu:

> It doesn't work in this case.  <fixup-asm-unistd.h> is used to undefine or
> redefine a syscall from <asm/unistd.h>.   The actual syscall numbers still
> come from <asm/unistd.h>.  In this case, the sycall number is missing from
> <asm/unistd_x32.h>.   My patch is a prerequisite for a new testcase:
>
> ../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c: In function ‘setup_ldt’:
> ../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c:258:14: error:
> ‘SYS_set_thread_area’ undeclared (first use in this function)
>   258 |  if (syscall(SYS_set_thread_area, &gdt_data16_desc) == 0) {
>       |              ^~~~~~~~~~~~~~~~~~~

Can you make it an internal test and use __NR_set_thread_area?

Thanks,
Florian

Re: [PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[H.J. Lu]

On Mon, Aug 24, 2020 at 6:23 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu:
>
> > It doesn't work in this case.  <fixup-asm-unistd.h> is used to undefine or
> > redefine a syscall from <asm/unistd.h>.   The actual syscall numbers still
> > come from <asm/unistd.h>.  In this case, the sycall number is missing from
> > <asm/unistd_x32.h>.   My patch is a prerequisite for a new testcase:
> >
> > ../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c: In function ‘setup_ldt’:
> > ../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c:258:14: error:
> > ‘SYS_set_thread_area’ undeclared (first use in this function)
> >   258 |  if (syscall(SYS_set_thread_area, &gdt_data16_desc) == 0) {
> >       |              ^~~~~~~~~~~~~~~~~~~
>
> Can you make it an internal test and use __NR_set_thread_area?
>

Like?

#if !defined(__NR_set_thread_area) && defined(__x86_64__) && defined(__ILP32__)
/* X32 uses the same 64-bit syscall interface for set_thread_area.  */
# define __NR_set_thread_area (__X32_SYSCALL_BIT + 205)
#endif


-- 
H.J.

Re: [PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[Florian Weimer]

* H. J. Lu:

> On Mon, Aug 24, 2020 at 6:23 AM Florian Weimer <fweimer@redhat.com> wrote:
>>
>> * H. J. Lu:
>>
>> > It doesn't work in this case.  <fixup-asm-unistd.h> is used to undefine or
>> > redefine a syscall from <asm/unistd.h>.   The actual syscall numbers still
>> > come from <asm/unistd.h>.  In this case, the sycall number is missing from
>> > <asm/unistd_x32.h>.   My patch is a prerequisite for a new testcase:
>> >
>> > ../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c: In function ‘setup_ldt’:
>> > ../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c:258:14: error:
>> > ‘SYS_set_thread_area’ undeclared (first use in this function)
>> >   258 |  if (syscall(SYS_set_thread_area, &gdt_data16_desc) == 0) {
>> >       |              ^~~~~~~~~~~~~~~~~~~
>>
>> Can you make it an internal test and use __NR_set_thread_area?
>>
>
> Like?
>
> #if !defined(__NR_set_thread_area) && defined(__x86_64__) && defined(__ILP32__)
> /* X32 uses the same 64-bit syscall interface for set_thread_area.  */
> # define __NR_set_thread_area (__X32_SYSCALL_BIT + 205)
> #endif

No, I neant using tests-internal, so that you get the built-in system
call table.

But is it really correct to add an unsupported system call definition
for the rest of glibc?  If this is just setting things up for a test,
maybe the __X32_SYSCALL_BIT hack is the right approach after all.
(I don't know the objective of this test.)

Thanks,
Florian

Re: [PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[H.J. Lu]

On Mon, Aug 24, 2020 at 10:17 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu:
>
> > On Mon, Aug 24, 2020 at 6:23 AM Florian Weimer <fweimer@redhat.com> wrote:
> >>
> >> * H. J. Lu:
> >>
> >> > It doesn't work in this case.  <fixup-asm-unistd.h> is used to undefine or
> >> > redefine a syscall from <asm/unistd.h>.   The actual syscall numbers still
> >> > come from <asm/unistd.h>.  In this case, the sycall number is missing from
> >> > <asm/unistd_x32.h>.   My patch is a prerequisite for a new testcase:
> >> >
> >> > ../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c: In function ‘setup_ldt’:
> >> > ../sysdeps/unix/sysv/linux/x86/tst-sigreturn-1.c:258:14: error:
> >> > ‘SYS_set_thread_area’ undeclared (first use in this function)
> >> >   258 |  if (syscall(SYS_set_thread_area, &gdt_data16_desc) == 0) {
> >> >       |              ^~~~~~~~~~~~~~~~~~~
> >>
> >> Can you make it an internal test and use __NR_set_thread_area?
> >>
> >
> > Like?
> >
> > #if !defined(__NR_set_thread_area) && defined(__x86_64__) && defined(__ILP32__)
> > /* X32 uses the same 64-bit syscall interface for set_thread_area.  */
> > # define __NR_set_thread_area (__X32_SYSCALL_BIT + 205)
> > #endif
>
> No, I neant using tests-internal, so that you get the built-in system
> call table.

Since __NR_set_thread_area may not be defined in the kernel header file,
move the test to tests-internal doesn't solve the problem.

> But is it really correct to add an unsupported system call definition
> for the rest of glibc?  If this is just setting things up for a test,
> maybe the __X32_SYSCALL_BIT hack is the right approach after all.
> (I don't know the objective of this test.)

set_thread_area is supported on x32.  The only thing missing is

#define __NR_set_thread_area (__X32_SYSCALL_BIT + 205)

in <asm/unistd_x32.h>.

Should I update my original patch to

#define __NR_set_thread_area (__X32_SYSCALL_BIT + 205)

-- 
H.J.

Re: [PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[Florian Weimer]

* H. J. Lu:

> Since __NR_set_thread_area may not be defined in the kernel header file,
> move the test to tests-internal doesn't solve the problem.

I expect that internal tests use the built-in system call tables, so
<fixup-asm-unistd.h> should be effective for them (indirectly, after
regenerating the tables).

>> But is it really correct to add an unsupported system call definition
>> for the rest of glibc?  If this is just setting things up for a test,
>> maybe the __X32_SYSCALL_BIT hack is the right approach after all.
>> (I don't know the objective of this test.)
>
> set_thread_area is supported on x32.  The only thing missing is
>
> #define __NR_set_thread_area (__X32_SYSCALL_BIT + 205)
>
> in <asm/unistd_x32.h>.
>
> Should I update my original patch to
>
> #define __NR_set_thread_area (__X32_SYSCALL_BIT + 205)

But set_thread_area is not supported for application use, so it's an
internal/whitebox test no matter what.

What exactly are you trying to test?

Thanks,
Florian

Re: [PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[H.J. Lu]

On Mon, Aug 24, 2020 at 12:10 PM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu:
>
> > Since __NR_set_thread_area may not be defined in the kernel header file,
> > move the test to tests-internal doesn't solve the problem.
>
> I expect that internal tests use the built-in system call tables, so
> <fixup-asm-unistd.h> should be effective for them (indirectly, after
> regenerating the tables).

<fixup-asm-unistd.h> can't be used to add a syscal number.

> >> But is it really correct to add an unsupported system call definition
> >> for the rest of glibc?  If this is just setting things up for a test,
> >> maybe the __X32_SYSCALL_BIT hack is the right approach after all.
> >> (I don't know the objective of this test.)
> >
> > set_thread_area is supported on x32.  The only thing missing is
> >
> > #define __NR_set_thread_area (__X32_SYSCALL_BIT + 205)
> >
> > in <asm/unistd_x32.h>.
> >
> > Should I update my original patch to
> >
> > #define __NR_set_thread_area (__X32_SYSCALL_BIT + 205)
>
> But set_thread_area is not supported for application use, so it's an
> internal/whitebox test no matter what.

True.

> What exactly are you trying to test?

I am putting tools/testing/selftests/x86/sigreturn.c from Linux kernel
into glibc to test a new arch_prctl syscall for CET:

    ARCH_X86_CET_MMAP_SHSTK:

    /* Allocate a new shadow stack with unsigned long long *addr:
         IN: requested shadow stack size: addr[0].
         IN: The mmap flags: addr[1].
             1. MAP_32BIT
             2. MAP_POPULATE
         OUT: allocated shadow stack address: *addr.
     */

-- 
H.J.

Re: [PATCH] x32: Add <asm/unistd_x32.h> and regenerate arch-syscall.h

[Florian Weimer]

* H. J. Lu:

> I am putting tools/testing/selftests/x86/sigreturn.c from Linux kernel
> into glibc to test a new arch_prctl syscall for CET:
>
>     ARCH_X86_CET_MMAP_SHSTK:
>
>     /* Allocate a new shadow stack with unsigned long long *addr:
>          IN: requested shadow stack size: addr[0].
>          IN: The mmap flags: addr[1].
>              1. MAP_32BIT
>              2. MAP_POPULATE
>          OUT: allocated shadow stack address: *addr.
>      */

This patch works for me.

Thanks,
Flroian

diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
index 16b768d8ba..2cd35c120b 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
@@ -3,6 +3,8 @@ default-abi := x32
 
 ifeq ($(subdir),misc)
 sysdep_routines += arch_prctl
+
+tests-internal += tst-set_thread_area
 endif
 
 ifeq ($(subdir),conform)
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h b/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
index 1a701c1472..7b64b1fa0c 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
@@ -260,6 +260,7 @@
 #define __NR_sendto 1073741868
 #define __NR_set_mempolicy 1073742062
 #define __NR_set_robust_list 1073742354
+#define __NR_set_thread_area 1073742029
 #define __NR_set_tid_address 1073742042
 #define __NR_setdomainname 1073741995
 #define __NR_setfsgid 1073741947
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
new file mode 100644
index 0000000000..984f948626
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
@@ -0,0 +1,3 @@
+#ifndef __NR_set_thread_area
+# define __NR_set_thread_area 1073742029
+#endif
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/tst-set_thread_area.c b/sysdeps/unix/sysv/linux/x86_64/x32/tst-set_thread_area.c
new file mode 100644
index 0000000000..ff2249d343
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/tst-set_thread_area.c
@@ -0,0 +1,9 @@
+#include <sys/syscall.h>
+
+static int
+do_test (void)
+{
+  return __NR_set_thread_area != 0;
+}
+
+#include <support/test-driver.c>

[PATCH] x32: Add <fixup-asm-unistd.h> and regenerate arch-syscall.h

[H.J. Lu]

[-- Attachment #1: Type: text/plain, Size: 2483 bytes --]

On Tue, Aug 25, 2020 at 3:50 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu:
>
> > I am putting tools/testing/selftests/x86/sigreturn.c from Linux kernel
> > into glibc to test a new arch_prctl syscall for CET:
> >
> >     ARCH_X86_CET_MMAP_SHSTK:
> >
> >     /* Allocate a new shadow stack with unsigned long long *addr:
> >          IN: requested shadow stack size: addr[0].
> >          IN: The mmap flags: addr[1].
> >              1. MAP_32BIT
> >              2. MAP_POPULATE
> >          OUT: allocated shadow stack address: *addr.
> >      */
>
> This patch works for me.
>
> Thanks,
> Flroian
>
> diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
> index 16b768d8ba..2cd35c120b 100644
> --- a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
> +++ b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
> @@ -3,6 +3,8 @@ default-abi := x32
>
>  ifeq ($(subdir),misc)
>  sysdep_routines += arch_prctl
> +
> +tests-internal += tst-set_thread_area
>  endif
>
>  ifeq ($(subdir),conform)
> diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h b/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
> index 1a701c1472..7b64b1fa0c 100644
> --- a/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
> +++ b/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
> @@ -260,6 +260,7 @@
>  #define __NR_sendto 1073741868
>  #define __NR_set_mempolicy 1073742062
>  #define __NR_set_robust_list 1073742354
> +#define __NR_set_thread_area 1073742029
>  #define __NR_set_tid_address 1073742042
>  #define __NR_setdomainname 1073741995
>  #define __NR_setfsgid 1073741947
> diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
> new file mode 100644
> index 0000000000..984f948626
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
> @@ -0,0 +1,3 @@
> +#ifndef __NR_set_thread_area
> +# define __NR_set_thread_area 1073742029
> +#endif
> diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/tst-set_thread_area.c b/sysdeps/unix/sysv/linux/x86_64/x32/tst-set_thread_area.c
> new file mode 100644
> index 0000000000..ff2249d343
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/x86_64/x32/tst-set_thread_area.c
> @@ -0,0 +1,9 @@
> +#include <sys/syscall.h>
> +
> +static int
> +do_test (void)
> +{
> +  return __NR_set_thread_area != 0;
> +}
> +
> +#include <support/test-driver.c>
>

Here is the updated patch.  OK for master?

Thanks.

-- 
H.J.

[-- Attachment #2: 0001-x32-Add-fixup-asm-unistd.h-and-regenerate-arch-sysca.patch --]
[-- Type: application/x-patch, Size: 4614 bytes --]

Re: [PATCH] x32: Add <fixup-asm-unistd.h> and regenerate arch-syscall.h

[Florian Weimer]

* H. J. Lu via Libc-alpha:

> diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
> index 16b768d8ba..2cd35c120b 100644
> --- a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
> +++ b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
> @@ -3,6 +3,8 @@ default-abi := x32
>  
>  ifeq ($(subdir),misc)
>  sysdep_routines += arch_prctl
> +
> +tests-internal += tst-set_thread_area
>  endif

I do not think the test is valuable.  I just added it to show that
things do actually compile with older Linux headers because you didn't
believe me. 8-)

> diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
> new file mode 100644
> index 0000000000..01d1f448ca
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h

> +/* X32 uses the same 64-bit syscall interface for set_thread_area.   */
> +#ifndef __NR_set_thread_area
> +# define __NR_set_thread_area 1073742029
> +#endif

I think the comment should reference the Linux version in which the
missing system call was fixed.

Thanks,
Florian

Re: [PATCH] x32: Add <fixup-asm-unistd.h> and regenerate arch-syscall.h

[H.J. Lu]

[-- Attachment #1: Type: text/plain, Size: 1423 bytes --]

On Wed, Aug 26, 2020 at 2:35 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu via Libc-alpha:
>
> > diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
> > index 16b768d8ba..2cd35c120b 100644
> > --- a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
> > +++ b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile
> > @@ -3,6 +3,8 @@ default-abi := x32
> >
> >  ifeq ($(subdir),misc)
> >  sysdep_routines += arch_prctl
> > +
> > +tests-internal += tst-set_thread_area
> >  endif
>
> I do not think the test is valuable.  I just added it to show that
> things do actually compile with older Linux headers because you didn't
> believe me. 8-)

Removed.

> > diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
> > new file mode 100644
> > index 0000000000..01d1f448ca
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
>
> > +/* X32 uses the same 64-bit syscall interface for set_thread_area.   */
> > +#ifndef __NR_set_thread_area
> > +# define __NR_set_thread_area 1073742029
> > +#endif
>
> I think the comment should reference the Linux version in which the
> missing system call was fixed.
>

Given that set_thread_area isn't for user application, I don't know when
my fix will be merged into the upstream kernel.

Here is the updated patch.   OK for master?

-- 
H.J.

[-- Attachment #2: 0001-x32-Add-fixup-asm-unistd.h-and-regenerate-arch-sysca.patch --]
[-- Type: text/x-patch, Size: 2794 bytes --]

From 630e831b73dd9c7d893699b0016fd8af900e237f Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Tue, 25 Aug 2020 05:35:45 -0700
Subject: [PATCH] x32: Add <fixup-asm-unistd.h> and regenerate arch-syscall.h

X32 uses the same 64-bit syscall interface for set_thread_area.  But
__NR_set_thread_area is missing from <asm/unistd_x32.h>.  A kernel patch
was submitted:

From 7b05d5b43ae2545e0d4a3edb24205d18bc883626 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Sat, 15 Aug 2020 10:34:00 -0700
Subject: [PATCH] x86-64: Enable x32 set_thread_area

X32 uses the common 64-bit syscall interface for set_thread_area.  Add
<fixup-asm-unistd.h> to provide __NR_set_thread_area.

Co-authored-by: Florian Weimer <fweimer@redhat.com>
---
 .../unix/sysv/linux/x86_64/x32/arch-syscall.h |  1 +
 .../sysv/linux/x86_64/x32/fixup-asm-unistd.h  | 21 +++++++++++++++++++
 2 files changed, 22 insertions(+)
 create mode 100644 sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h

diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h b/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
index 1a701c1472..7b64b1fa0c 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/arch-syscall.h
@@ -260,6 +260,7 @@
 #define __NR_sendto 1073741868
 #define __NR_set_mempolicy 1073742062
 #define __NR_set_robust_list 1073742354
+#define __NR_set_thread_area 1073742029
 #define __NR_set_tid_address 1073742042
 #define __NR_setdomainname 1073741995
 #define __NR_setfsgid 1073741947
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
new file mode 100644
index 0000000000..01d1f448ca
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/fixup-asm-unistd.h
@@ -0,0 +1,21 @@
+/* Regularize <asm/unistd.h> definitions.  X32 version.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* X32 uses the same 64-bit syscall interface for set_thread_area.   */
+#ifndef __NR_set_thread_area
+# define __NR_set_thread_area 1073742029
+#endif
-- 
2.26.2

Re: [PATCH] x32: Add <fixup-asm-unistd.h> and regenerate arch-syscall.h

[Florian Weimer]

* H. J. Lu:

> Given that set_thread_area isn't for user application, I don't know when
> my fix will be merged into the upstream kernel.
>
> Here is the updated patch.   OK for master?

Yes, this looks okay to me.

Thanks,
Florian