arm64: rename COMPAT to AARCH32_EL0

hulk inclusion
category: feature
bugzilla: NA
CVE: NA
---------------------------

In this patchset ILP32 ABI support is added. Additionally to AARCH32,
which is binary-compatible with ARM, ILP32 is (mostly) ABI-compatible.

From now, AARCH32_EL0 (former COMPAT) config option means the support of
AARCH32 userspace, and ARM64_ILP32 - support of ILP32 ABI (see following
patches). COMPAT indicates that one of them or both is enabled.

Where needed, CONFIG_COMPAT is changed over to use CONFIG_AARCH32_EL0
instead.
Reviewed-by: NDavid Daney <ddaney@caviumnetworks.com>
Signed-off-by: NAndrew Pinski <Andrew.Pinski@caviumnetworks.com>
Signed-off-by: NYury Norov <ynorov@caviumnetworks.com>
Signed-off-by: NPhilipp Tomsich <philipp.tomsich@theobroma-systems.com>
Signed-off-by: NChristoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: NBamvor Jian Zhang <bamv2005@gmail.com>

 Conflicts:
	arch/arm64/kernel/cpufeature.c
[wangxiongfeng: conflicts below 'arm64_cpu_capabilities
compat_elf_hwcaps' because we have the follow commit.
119703e850 arm64: cpufeature: Set the FP/SIMD compat HWCAP bits properly
Fix conflicts by only changing 'CONFIG_COMPAT' to 'CONFIG_AARCH32_EL0']
Signed-off-by: NXiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: NHanjun Guo &lt;guohanjun@huawei.com <mailto:guohanjun@huawei.com&gt;>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

arch/arm64/Kconfig

@@ -444,7 +444,7 @@ config ARM64_ERRATUM_834220
 
 config ARM64_ERRATUM_845719
 	bool "Cortex-A53: 845719: a load might read incorrect data"
-	depends on COMPAT
+	depends on AARCH32_EL0
 	default y
 	help
 	  This option adds an alternative code sequence to work around ARM
@@ -1039,7 +1039,7 @@ config ARM64_SSBD
 
 menuconfig ARMV8_DEPRECATED
 	bool "Emulate deprecated/obsolete ARMv8 instructions"
-	depends on COMPAT
+	depends on AARCH32_EL0
 	depends on SYSCTL
 	help
 	  Legacy software support may require certain instructions
@@ -1456,7 +1456,12 @@ config DMI
 endmenu
 
 config COMPAT
+	def_bool y
+	depends on AARCH32_EL0
+
+config AARCH32_EL0
 	bool "Kernel support for 32-bit EL0"
+	def_bool y
 	depends on ARM64_4K_PAGES || EXPERT
 	select COMPAT_BINFMT_ELF if BINFMT_ELF
 	select HAVE_UID16

arch/arm64/include/asm/fpsimd.h

@@ -29,7 +29,7 @@
 #include <linux/init.h>
 #include <linux/stddef.h>
 
-#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
+#if defined(__KERNEL__) && defined(CONFIG_AARCH32_EL0)
 /* Masks for extracting the FPSR and FPCR from the FPSCR */
 #define VFP_FPSCR_STAT_MASK	0xf800009f
 #define VFP_FPSCR_CTRL_MASK	0x07f79f00

arch/arm64/include/asm/hwcap.h

@@ -46,7 +46,7 @@
  */
 #define ELF_HWCAP		(elf_hwcap)
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 #define COMPAT_ELF_HWCAP	(compat_elf_hwcap)
 #define COMPAT_ELF_HWCAP2	(compat_elf_hwcap2)
 extern unsigned int compat_elf_hwcap, compat_elf_hwcap2;
@@ -54,7 +54,7 @@ extern unsigned int compat_elf_hwcap, compat_elf_hwcap2;
 
 enum {
 	CAP_HWCAP = 1,
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	CAP_COMPAT_HWCAP,
 	CAP_COMPAT_HWCAP2,
 #endif

arch/arm64/include/asm/processor.h

@@ -149,7 +149,7 @@ static inline void arch_thread_struct_whitelist(unsigned long *offset,
 	*size = sizeof_field(struct thread_struct, uw);
 }
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 #define task_user_tls(t)						\
 ({									\
 	unsigned long *__tls;						\
@@ -202,7 +202,7 @@ static inline void start_thread(struct pt_regs *regs, unsigned long pc,
 	regs->sp = sp;
 }
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
 				       unsigned long sp)
 {

arch/arm64/include/asm/ptrace.h

@@ -207,7 +207,7 @@ static inline void forget_syscall(struct pt_regs *regs)
 
 #define arch_has_single_step()	(1)
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 #define compat_thumb_mode(regs) \
 	(((regs)->pstate & PSR_AA32_T_BIT))
 #else

arch/arm64/include/asm/seccomp.h

@@ -13,7 +13,7 @@
 
 #include <asm/unistd.h>
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 #define __NR_seccomp_read_32		__NR_compat_read
 #define __NR_seccomp_write_32		__NR_compat_write
 #define __NR_seccomp_exit_32		__NR_compat_exit

arch/arm64/include/asm/signal32.h

@@ -17,7 +17,9 @@
 #define __ASM_SIGNAL32_H
 
 #ifdef __KERNEL__
-#ifdef CONFIG_COMPAT
+
+#ifdef CONFIG_AARCH32_EL0
+
 #include <linux/compat.h>
 
 #define AARCH32_KERN_SIGRET_CODE_OFFSET	0x500
@@ -45,6 +47,6 @@ static inline int compat_setup_rt_frame(int usig, struct ksignal *ksig, sigset_t
 static inline void compat_setup_restart_syscall(struct pt_regs *regs)
 {
 }
-#endif /* CONFIG_COMPAT */
+#endif /* CONFIG_AARCH32_EL0 */
 #endif /* __KERNEL__ */
 #endif /* __ASM_SIGNAL32_H */

arch/arm64/include/asm/syscall.h

@@ -24,7 +24,7 @@ typedef long (*syscall_fn_t)(const struct pt_regs *regs);
 
 extern const syscall_fn_t sys_call_table[];
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 extern const syscall_fn_t compat_sys_call_table[];
 #endif
 

arch/arm64/include/asm/unistd.h

@@ -13,7 +13,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 #define __ARCH_WANT_COMPAT_STAT64
 #define __ARCH_WANT_SYS_GETHOSTNAME
 #define __ARCH_WANT_SYS_PAUSE

arch/arm64/kernel/Makefile

@@ -27,7 +27,7 @@ OBJCOPYFLAGS := --prefix-symbols=__efistub_
 $(obj)/%.stub.o: $(obj)/%.o FORCE
 	$(call if_changed,objcopy)
 
-arm64-obj-$(CONFIG_COMPAT)		+= sys32.o kuser32.o signal32.o 	\
+arm64-obj-$(CONFIG_AARCH32_EL0)		+= sys32.o kuser32.o signal32.o 	\
 					   sys_compat.o
 arm64-obj-$(CONFIG_FUNCTION_TRACER)	+= ftrace.o entry-ftrace.o
 arm64-obj-$(CONFIG_MODULES)		+= arm64ksyms.o module.o

arch/arm64/kernel/asm-offsets.c

@@ -70,7 +70,7 @@ int main(void)
   DEFINE(S_X28,			offsetof(struct pt_regs, regs[28]));
   DEFINE(S_LR,			offsetof(struct pt_regs, regs[30]));
   DEFINE(S_SP,			offsetof(struct pt_regs, sp));
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
   DEFINE(S_COMPAT_SP,		offsetof(struct pt_regs, compat_sp));
 #endif
   DEFINE(S_PSTATE,		offsetof(struct pt_regs, pstate));

arch/arm64/kernel/cpufeature.c

@@ -38,7 +38,7 @@
 unsigned long elf_hwcap __read_mostly;
 EXPORT_SYMBOL_GPL(elf_hwcap);
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 #define COMPAT_ELF_HWCAP_DEFAULT	\
 				(COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
 				 COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
@@ -1598,7 +1598,7 @@ static bool compat_has_neon(const struct arm64_cpu_capabilities *cap, int scope)
 #endif
 
 static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	HWCAP_CAP_MATCH(compat_has_neon, CAP_COMPAT_HWCAP, COMPAT_HWCAP_NEON),
 	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDFMAC_SHIFT, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv4),
 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
@@ -1619,7 +1619,7 @@ static void __init cap_set_elf_hwcap(const struct arm64_cpu_capabilities *cap)
 	case CAP_HWCAP:
 		elf_hwcap |= cap->hwcap;
 		break;
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	case CAP_COMPAT_HWCAP:
 		compat_elf_hwcap |= (u32)cap->hwcap;
 		break;
@@ -1642,7 +1642,7 @@ static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap)
 	case CAP_HWCAP:
 		rc = (elf_hwcap & cap->hwcap) != 0;
 		break;
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	case CAP_COMPAT_HWCAP:
 		rc = (compat_elf_hwcap & (u32)cap->hwcap) != 0;
 		break;

arch/arm64/kernel/cpuinfo.c

@@ -86,7 +86,7 @@ static const char *const hwcap_str[] = {
 	NULL
 };
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 static const char *const compat_hwcap_str[] = {
 	"swp",
 	"half",
@@ -121,7 +121,7 @@ static const char *const compat_hwcap2_str[] = {
 	"crc32",
 	NULL
 };
-#endif /* CONFIG_COMPAT */
+#endif /* CONFIG_AARCH32_EL0 */
 
 static int c_show(struct seq_file *m, void *v)
 {
@@ -154,7 +154,7 @@ static int c_show(struct seq_file *m, void *v)
 		 */
 		seq_puts(m, "Features\t:");
 		if (compat) {
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 			for (j = 0; compat_hwcap_str[j]; j++)
 				if (compat_elf_hwcap & (1 << j))
 					seq_printf(m, " %s", compat_hwcap_str[j]);
@@ -162,7 +162,7 @@ static int c_show(struct seq_file *m, void *v)
 			for (j = 0; compat_hwcap2_str[j]; j++)
 				if (compat_elf_hwcap2 & (1 << j))
 					seq_printf(m, " %s", compat_hwcap2_str[j]);
-#endif /* CONFIG_COMPAT */
+#endif /* CONFIG_AARCH32_EL0 */
 		} else {
 			for (j = 0; hwcap_str[j]; j++)
 				if (elf_hwcap & (1 << j))

arch/arm64/kernel/entry.S

@@ -489,7 +489,7 @@ ENTRY(vectors)
 	kernel_ventry	0, fiq_invalid			// FIQ 64-bit EL0
 	kernel_ventry	0, error			// Error 64-bit EL0
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	kernel_ventry	0, sync_compat, 32		// Synchronous 32-bit EL0
 	kernel_ventry	0, irq_compat, 32		// IRQ 32-bit EL0
 	kernel_ventry	0, fiq_invalid_compat, 32	// FIQ 32-bit EL0
@@ -558,7 +558,7 @@ el0_error_invalid:
 	inv_entry 0, BAD_ERROR
 ENDPROC(el0_error_invalid)
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 el0_fiq_invalid_compat:
 	inv_entry 0, BAD_FIQ, 32
 ENDPROC(el0_fiq_invalid_compat)
@@ -759,7 +759,7 @@ el0_sync:
 	b.ge	el0_dbg
 	b	el0_inv
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	.align	6
 el0_sync_compat:
 	kernel_entry 0, 32

arch/arm64/kernel/head.S

@@ -542,7 +542,7 @@ set_hcr:
 	msr	vpidr_el2, x0
 	msr	vmpidr_el2, x1
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	msr	hstr_el2, xzr			// Disable CP15 traps to EL2
 #endif
 

arch/arm64/kernel/perf_callchain.c

@@ -59,7 +59,7 @@ user_backtrace(struct frame_tail __user *tail,
 	return buftail.fp;
 }
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 /*
  * The registers we're interested in are at the end of the variable
  * length saved register structure. The fp points at the end of this
@@ -104,7 +104,7 @@ compat_user_backtrace(struct compat_frame_tail __user *tail,
 
 	return (struct compat_frame_tail __user *)compat_ptr(buftail.fp) - 1;
 }
-#endif /* CONFIG_COMPAT */
+#endif /* CONFIG_AARCH32_EL0 */
 
 void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
 			 struct pt_regs *regs)
@@ -126,7 +126,7 @@ void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
 		       tail && !((unsigned long)tail & 0xf))
 			tail = user_backtrace(tail, entry);
 	} else {
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 		/* AARCH32 compat mode */
 		struct compat_frame_tail __user *tail;
 

arch/arm64/kernel/ptrace.c

@@ -190,7 +190,7 @@ static void ptrace_hbptriggered(struct perf_event *bp,
 	info.si_code	= TRAP_HWBKPT;
 	info.si_addr	= (void __user *)(bkpt->trigger);
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	if (is_compat_task()) {
 		int si_errno = 0;
 		int i;
@@ -1060,7 +1060,9 @@ static const struct user_regset_view user_aarch64_view = {
 	.regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
 };
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
+#include <linux/compat.h>
+
 enum compat_regset {
 	REGSET_COMPAT_GPR,
 	REGSET_COMPAT_VFP,
@@ -1603,11 +1605,11 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 
 	return ret;
 }
-#endif /* CONFIG_COMPAT */
+#endif /* CONFIG_AARCH32_EL0 */
 
 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 {
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	/*
 	 * Core dumping of 32-bit tasks or compat ptrace requests must use the
 	 * user_aarch32_view compatible with arm32. Native ptrace requests on

arch/arm64/kernel/syscall.c

@@ -19,7 +19,7 @@ long sys_ni_syscall(void);
 
 static long do_ni_syscall(struct pt_regs *regs, int scno)
 {
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	long ret;
 	if (is_compat_task()) {
 		ret = compat_arm_syscall(regs, scno);
@@ -163,7 +163,7 @@ asmlinkage void el0_svc_handler(struct pt_regs *regs)
 	el0_svc_common(regs, regs->regs[8], __NR_syscalls, sys_call_table);
 }
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 asmlinkage void el0_svc_compat_handler(struct pt_regs *regs)
 {
 	el0_svc_common(regs, regs->regs[7], __NR_compat_syscalls,

arch/arm64/kernel/vdso.c

@@ -49,7 +49,7 @@ static union {
 } vdso_data_store __page_aligned_data;
 struct vdso_data *vdso_data = &vdso_data_store.data;
 
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 /*
  * Create and map the vectors page for AArch32 tasks.
  */
@@ -108,7 +108,7 @@ int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp)
 
 	return PTR_ERR_OR_ZERO(ret);
 }
-#endif /* CONFIG_COMPAT */
+#endif /* CONFIG_AARCH32_EL0 */
 
 static int vdso_mremap(const struct vm_special_mapping *sm,
 		struct vm_area_struct *new_vma)

drivers/clocksource/arm_arch_timer.c

@@ -821,7 +821,7 @@ static void arch_timer_evtstrm_enable(int divider)
 			| ARCH_TIMER_VIRT_EVT_EN;
 	arch_timer_set_cntkctl(cntkctl);
 	elf_hwcap |= HWCAP_EVTSTRM;
-#ifdef CONFIG_COMPAT
+#ifdef CONFIG_AARCH32_EL0
 	compat_elf_hwcap |= COMPAT_HWCAP_EVTSTRM;
 #endif
 	cpumask_set_cpu(smp_processor_id(), &evtstrm_available);