arm64: compat: Check for AArch32 state

Make sure we have AArch32 state available for running COMPAT
binaries and also for switching the personality to PER_LINUX32.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
[ Added cap bit, checks for HWCAP, personality ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Suzuki K Poulose 2016-04-18 10:28:37 +01:00 committed by Will Deacon
parent 042446a31e
commit 643d703d2d
3 changed files with 17 additions and 3 deletions

View File

@ -177,7 +177,8 @@ typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_ELF_NGREG];
/* AArch32 EABI. */
#define EF_ARM_EABI_MASK 0xff000000
#define compat_elf_check_arch(x) (((x)->e_machine == EM_ARM) && \
#define compat_elf_check_arch(x) (system_supports_32bit_el0() && \
((x)->e_machine == EM_ARM) && \
((x)->e_flags & EF_ARM_EABI_MASK))
#define compat_start_thread compat_start_thread

View File

@ -987,7 +987,8 @@ void verify_local_cpu_capabilities(void)
verify_local_cpu_features(arm64_features);
verify_local_elf_hwcaps(arm64_elf_hwcaps);
verify_local_elf_hwcaps(compat_elf_hwcaps);
if (system_supports_32bit_el0())
verify_local_elf_hwcaps(compat_elf_hwcaps);
}
static void __init setup_feature_capabilities(void)
@ -1004,7 +1005,9 @@ void __init setup_cpu_features(void)
/* Set the CPU feature capabilies */
setup_feature_capabilities();
setup_elf_hwcaps(arm64_elf_hwcaps);
setup_elf_hwcaps(compat_elf_hwcaps);
if (system_supports_32bit_el0())
setup_elf_hwcaps(compat_elf_hwcaps);
/* Advertise that we have computed the system capabilities */
set_sys_caps_initialised();

View File

@ -25,6 +25,7 @@
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/syscalls.h>
#include <asm/cpufeature.h>
asmlinkage long sys_mmap(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
@ -36,11 +37,20 @@ asmlinkage long sys_mmap(unsigned long addr, unsigned long len,
return sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
}
SYSCALL_DEFINE1(arm64_personality, unsigned int, personality)
{
if (personality(personality) == PER_LINUX32 &&
!system_supports_32bit_el0())
return -EINVAL;
return sys_personality(personality);
}
/*
* Wrappers to pass the pt_regs argument.
*/
asmlinkage long sys_rt_sigreturn_wrapper(void);
#define sys_rt_sigreturn sys_rt_sigreturn_wrapper
#define sys_personality sys_arm64_personality
#undef __SYSCALL
#define __SYSCALL(nr, sym) [nr] = sym,