linux.git/arch/arm64/kernel/entry32.S, branch v4.11 Linux kernel source tree arm64: entry32: remove pointless register assignment 2015-07-10T15:47:13+00:00 Mark Rutland mark.rutland@arm.com 2015-07-10T14:46:32+00:00 ad2daa85bd50b7ff5c851b80a0b813bdc8d14f8e We currently set x27 in compat_sys_sigreturn_wrapper and compat_sys_rt_sigreturn_wrapper, similarly to what we do with r8/why on 32-bit ARM, in an attempt to prevent sigreturns from being restarted. However, on arm64 we have always used pt_regs::syscallno for syscall restarting (for both native and compat tasks), and x27 is never inspected again before being overwritten in kernel_exit. This patch removes the pointless register assignments. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
We currently set x27 in compat_sys_sigreturn_wrapper and
compat_sys_rt_sigreturn_wrapper, similarly to what we do with r8/why on
32-bit ARM, in an attempt to prevent sigreturns from being restarted.

However, on arm64 we have always used pt_regs::syscallno for syscall
restarting (for both native and compat tasks), and x27 is never
inspected again before being overwritten in kernel_exit.

This patch removes the pointless register assignments.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: fix implementation of mmap2 compat syscall 2015-03-19T10:43:51+00:00 Andreas Schwab schwab@suse.de 2015-03-16T16:32:22+00:00 18ccb0cab49ef7868eaf9504f257e1a84683dbbd The arm mmap2 syscall takes the offset in units of 4K, thus with 64K pages the offset needs to be scaled to units of pages. Signed-off-by: Andreas Schwab <schwab@suse.de> Signed-off-by: Alexander Graf <agraf@suse.de> [will: removed redundant lr parameter, localised PAGE_SHIFT #if check] Signed-off-by: Will Deacon <will.deacon@arm.com> 
The arm mmap2 syscall takes the offset in units of 4K, thus with 64K pages
the offset needs to be scaled to units of pages.

Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
[will: removed redundant lr parameter, localised PAGE_SHIFT #if check]
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm64: Implement the compat_sys_call_table in C 2015-01-27T09:38:07+00:00 Catalin Marinas catalin.marinas@arm.com 2015-01-06T16:42:32+00:00 0156411b1828771c09c92f034e7b81f702b84f07 Unlike the sys_call_table[], the compat one was implemented in sys32.S making it impossible to notice discrepancies between the number of compat syscalls and the __NR_compat_syscalls macro, the latter having to be defined in asm/unistd.h as including asm/unistd32.h would cause conflicts on __NR_* definitions. With this patch, incorrect __NR_compat_syscalls values will result in a build-time error. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Suggested-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> 
Unlike the sys_call_table[], the compat one was implemented in sys32.S
making it impossible to notice discrepancies between the number of
compat syscalls and the __NR_compat_syscalls macro, the latter having to
be defined in asm/unistd.h as including asm/unistd32.h would cause
conflicts on __NR_* definitions. With this patch, incorrect
__NR_compat_syscalls values will result in a build-time error.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>