linux/arch/x86/um
Dave Hansen da20ab3518 x86/entry: Use SYSCALL_DEFINE() macros for sys_modify_ldt()
We do not have tracepoints for sys_modify_ldt() because we define
it directly instead of using the normal SYSCALL_DEFINEx() macros.

However, there is a reason sys_modify_ldt() does not use the macros:
it has an 'int' return type instead of 'unsigned long'.  This is
a bug, but it's a bug cemented in the ABI.

What does this mean?  If we return -EINVAL from a function that
returns 'int', we have 0x00000000ffffffea in %rax.  But, if we
return -EINVAL from a function returning 'unsigned long', we end
up with 0xffffffffffffffea in %rax, which is wrong.

To work around this and maintain the 'int' behavior while using
the SYSCALL_DEFINEx() macros, so we add a cast to 'unsigned int'
in both implementations of sys_modify_ldt().

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Brian Gerst <brgerst@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171018172107.1A79C532@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-20 10:37:33 +02:00
..
asm x86/arch_prctl: Rename 'code' argument to 'option' 2017-03-20 16:10:32 +01:00
os-Linux um: remove a stray tab 2017-09-13 22:36:27 +02:00
shared/sysdep um: Include kbuild.h instead of duplicating its macros 2017-05-03 22:36:56 +02:00
vdso x86/um: thin archives build fix 2017-06-30 09:03:05 +09:00
bugs_32.c
bugs_64.c
checksum_32.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
delay.c x86: Audit and remove any remaining unnecessary uses of module.h 2016-07-14 15:07:00 +02:00
elfcore.c switch elf_core_write_extra_data() to dump_emit() 2013-11-09 00:16:23 -05:00
fault.c um: don't compare a pointer to 0 2012-12-20 11:49:39 -08:00
Kconfig arch/um: make it work with defconfig and x86_64 2013-11-17 11:31:48 +01:00
ldt.c x86/entry: Use SYSCALL_DEFINE() macros for sys_modify_ldt() 2017-10-20 10:37:33 +02:00
Makefile Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-01 22:07:51 -07:00
mem_32.c um: Cleanup mem_32/64.c headers 2015-05-31 17:31:42 +02:00
mem_64.c um: Cleanup mem_32/64.c headers 2015-05-31 17:31:42 +02:00
ptrace_32.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
ptrace_64.c um: Fix PTRACE_POKEUSER on x86_64 2017-05-03 22:35:31 +02:00
ptrace_user.c
setjmp_32.S um: Avoid longjmp/setjmp symbol clashes with libpthread.a 2017-07-05 23:30:50 +02:00
setjmp_64.S um: Avoid longjmp/setjmp symbol clashes with libpthread.a 2017-07-05 23:30:50 +02:00
signal.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
stub_32.S um: Remove dead symbol from i386 syscall stub 2015-11-06 22:49:11 +01:00
stub_64.S um: Simplify STUB_DATA loading 2015-11-06 22:49:11 +01:00
stub_segv.c
sys_call_table_32.c x86/syscalls: Add syscall entry qualifiers 2016-01-29 09:46:38 +01:00
sys_call_table_64.c x86/syscalls: Add syscall entry qualifiers 2016-01-29 09:46:38 +01:00
syscalls_32.c x86/syscalls/32: Wire up arch_prctl on x86-32 2017-03-20 16:10:33 +01:00
syscalls_64.c um/arch_prctl: Fix fallout from x86 arch_prctl() rework 2017-03-21 10:08:29 +01:00
sysrq_32.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h> 2017-03-02 08:42:34 +01:00
sysrq_64.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h> 2017-03-02 08:42:34 +01:00
tls_32.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
tls_64.c um: Don't pollute kernel namespace with uapi 2015-06-25 22:44:11 +02:00
user-offsets.c um: Fix FP register size for XSTATE/XSAVE 2017-09-13 22:24:38 +02:00