Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "I'm safely chained back up to my desk, so please pull these arm64
  fixes for -rc1 that address some issues that cropped up during the
  merge window:

   - Prevent KASLR from mapping the top page of the virtual address
     space

   - Fix device-tree probing of SDEI driver

   - Fix incorrect register offset definition in Hisilicon DDRC PMU
     driver

   - Fix compilation issue with older binutils not liking unsigned
     immediates

   - Fix uapi headers so that libc can provide its own sigcontext
     definition

   - Fix handling of private compat syscalls

   - Hook up compat io_pgetevents() syscall for 32-bit tasks

   - Cleanup to arm64 Makefile (including now to avoid silly conflicts)"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: compat: Hook up io_pgetevents() for 32-bit tasks
  arm64: compat: Don't pull syscall number from regs in arm_compat_syscall
  arm64: compat: Avoid sending SIGILL for unallocated syscall numbers
  arm64/sve: Disentangle <uapi/asm/ptrace.h> from <uapi/asm/sigcontext.h>
  arm64/sve: ptrace: Fix SVE_PT_REGS_OFFSET definition
  drivers/perf: hisi: Fixup one DDRC PMU register offset
  arm64: replace arm64-obj-* in Makefile with obj-*
  arm64: kaslr: Reserve size of ARM64_MEMSTART_ALIGN in linear region
  firmware: arm_sdei: Fix DT platform device creation
  firmware: arm_sdei: fix wrong of_node_put() in init function
  arm64: entry: remove unused register aliases
  arm64: smp: Fix compilation error

arch/arm64/kernel/Makefile

@@ -12,7 +12,7 @@ CFLAGS_REMOVE_insn.o = -pg
 CFLAGS_REMOVE_return_address.o = -pg
 
 # Object file lists.
-arm64-obj-y		:= debug-monitors.o entry.o irq.o fpsimd.o		\
+obj-y			:= debug-monitors.o entry.o irq.o fpsimd.o		\
 			   entry-fpsimd.o process.o ptrace.o setup.o signal.o	\
 			   sys.o stacktrace.o time.o traps.o io.o vdso.o	\
 			   hyp-stub.o psci.o cpu_ops.o insn.o	\
@@ -27,41 +27,40 @@ OBJCOPYFLAGS := --prefix-symbols=__efistub_
 $(obj)/%.stub.o: $(obj)/%.o FORCE
 	$(call if_changed,objcopy)
 
-arm64-obj-$(CONFIG_COMPAT)		+= sys32.o kuser32.o signal32.o 	\
+obj-$(CONFIG_COMPAT)			+= sys32.o kuser32.o signal32.o 	\
 					   sys_compat.o
-arm64-obj-$(CONFIG_FUNCTION_TRACER)	+= ftrace.o entry-ftrace.o
-arm64-obj-$(CONFIG_MODULES)		+= module.o
-arm64-obj-$(CONFIG_ARM64_MODULE_PLTS)	+= module-plts.o
-arm64-obj-$(CONFIG_PERF_EVENTS)		+= perf_regs.o perf_callchain.o
-arm64-obj-$(CONFIG_HW_PERF_EVENTS)	+= perf_event.o
-arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)	+= hw_breakpoint.o
-arm64-obj-$(CONFIG_CPU_PM)		+= sleep.o suspend.o
-arm64-obj-$(CONFIG_CPU_IDLE)		+= cpuidle.o
-arm64-obj-$(CONFIG_JUMP_LABEL)		+= jump_label.o
-arm64-obj-$(CONFIG_KGDB)		+= kgdb.o
-arm64-obj-$(CONFIG_EFI)			+= efi.o efi-entry.stub.o		\
+obj-$(CONFIG_FUNCTION_TRACER)		+= ftrace.o entry-ftrace.o
+obj-$(CONFIG_MODULES)			+= module.o
+obj-$(CONFIG_ARM64_MODULE_PLTS)		+= module-plts.o
+obj-$(CONFIG_PERF_EVENTS)		+= perf_regs.o perf_callchain.o
+obj-$(CONFIG_HW_PERF_EVENTS)		+= perf_event.o
+obj-$(CONFIG_HAVE_HW_BREAKPOINT)	+= hw_breakpoint.o
+obj-$(CONFIG_CPU_PM)			+= sleep.o suspend.o
+obj-$(CONFIG_CPU_IDLE)			+= cpuidle.o
+obj-$(CONFIG_JUMP_LABEL)		+= jump_label.o
+obj-$(CONFIG_KGDB)			+= kgdb.o
+obj-$(CONFIG_EFI)			+= efi.o efi-entry.stub.o		\
 					   efi-rt-wrapper.o
-arm64-obj-$(CONFIG_PCI)			+= pci.o
-arm64-obj-$(CONFIG_ARMV8_DEPRECATED)	+= armv8_deprecated.o
-arm64-obj-$(CONFIG_ACPI)		+= acpi.o
-arm64-obj-$(CONFIG_ACPI_NUMA)		+= acpi_numa.o
-arm64-obj-$(CONFIG_ARM64_ACPI_PARKING_PROTOCOL)	+= acpi_parking_protocol.o
-arm64-obj-$(CONFIG_PARAVIRT)		+= paravirt.o
-arm64-obj-$(CONFIG_RANDOMIZE_BASE)	+= kaslr.o
-arm64-obj-$(CONFIG_HIBERNATION)		+= hibernate.o hibernate-asm.o
-arm64-obj-$(CONFIG_KEXEC_CORE)		+= machine_kexec.o relocate_kernel.o	\
+obj-$(CONFIG_PCI)			+= pci.o
+obj-$(CONFIG_ARMV8_DEPRECATED)		+= armv8_deprecated.o
+obj-$(CONFIG_ACPI)			+= acpi.o
+obj-$(CONFIG_ACPI_NUMA)			+= acpi_numa.o
+obj-$(CONFIG_ARM64_ACPI_PARKING_PROTOCOL)	+= acpi_parking_protocol.o
+obj-$(CONFIG_PARAVIRT)			+= paravirt.o
+obj-$(CONFIG_RANDOMIZE_BASE)		+= kaslr.o
+obj-$(CONFIG_HIBERNATION)		+= hibernate.o hibernate-asm.o
+obj-$(CONFIG_KEXEC_CORE)		+= machine_kexec.o relocate_kernel.o	\
 					   cpu-reset.o
-arm64-obj-$(CONFIG_KEXEC_FILE)		+= machine_kexec_file.o kexec_image.o
-arm64-obj-$(CONFIG_ARM64_RELOC_TEST)	+= arm64-reloc-test.o
+obj-$(CONFIG_KEXEC_FILE)		+= machine_kexec_file.o kexec_image.o
+obj-$(CONFIG_ARM64_RELOC_TEST)		+= arm64-reloc-test.o
 arm64-reloc-test-y := reloc_test_core.o reloc_test_syms.o
-arm64-obj-$(CONFIG_CRASH_DUMP)		+= crash_dump.o
-arm64-obj-$(CONFIG_CRASH_CORE)		+= crash_core.o
-arm64-obj-$(CONFIG_ARM_SDE_INTERFACE)	+= sdei.o
-arm64-obj-$(CONFIG_ARM64_SSBD)		+= ssbd.o
-arm64-obj-$(CONFIG_ARM64_PTR_AUTH)	+= pointer_auth.o
+obj-$(CONFIG_CRASH_DUMP)		+= crash_dump.o
+obj-$(CONFIG_CRASH_CORE)		+= crash_core.o
+obj-$(CONFIG_ARM_SDE_INTERFACE)		+= sdei.o
+obj-$(CONFIG_ARM64_SSBD)		+= ssbd.o
+obj-$(CONFIG_ARM64_PTR_AUTH)		+= pointer_auth.o
 
-obj-y					+= $(arm64-obj-y) vdso/ probes/
-obj-m					+= $(arm64-obj-m)
+obj-y					+= vdso/ probes/
 head-y					:= head.o
 extra-y					+= $(head-y) vmlinux.lds
 

arch/arm64/kernel/entry.S

@@ -392,17 +392,7 @@ alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0
 	mov	sp, x19
 	.endm
 
-/*
- * These are the registers used in the syscall handler, and allow us to
- * have in theory up to 7 arguments to a function - x0 to x6.
- *
- * x7 is reserved for the system call number in 32-bit mode.
- */
-wsc_nr	.req	w25		// number of system calls
-xsc_nr	.req	x25		// number of system calls (zero-extended)
-wscno	.req	w26		// syscall number
-xscno	.req	x26		// syscall number (zero-extended)
-stbl	.req	x27		// syscall table pointer
+/* GPRs used by entry code */
 tsk	.req	x28		// current thread_info
 
 /*

arch/arm64/kernel/sys_compat.c

@@ -66,12 +66,11 @@ do_compat_cache_op(unsigned long start, unsigned long end, int flags)
 /*
  * Handle all unrecognised system calls.
  */
-long compat_arm_syscall(struct pt_regs *regs)
+long compat_arm_syscall(struct pt_regs *regs, int scno)
 {
-	unsigned int no = regs->regs[7];
 	void __user *addr;
 
-	switch (no) {
+	switch (scno) {
 	/*
 	 * Flush a region from virtual address 'r0' to virtual address 'r1'
 	 * _exclusive_.  There is no alignment requirement on either address;
@@ -102,12 +101,12 @@ long compat_arm_syscall(struct pt_regs *regs)
 
 	default:
 		/*
-		 * Calls 9f00xx..9f07ff are defined to return -ENOSYS
+		 * Calls 0xf0xxx..0xf07ff are defined to return -ENOSYS
 		 * if not implemented, rather than raising SIGILL. This
 		 * way the calling program can gracefully determine whether
 		 * a feature is supported.
 		 */
-		if ((no & 0xffff) <= 0x7ff)
+		if (scno < __ARM_NR_COMPAT_END)
 			return -ENOSYS;
 		break;
 	}
@@ -116,6 +115,6 @@ long compat_arm_syscall(struct pt_regs *regs)
 		(compat_thumb_mode(regs) ? 2 : 4);
 
 	arm64_notify_die("Oops - bad compat syscall(2)", regs,
-			 SIGILL, ILL_ILLTRP, addr, no);
+			 SIGILL, ILL_ILLTRP, addr, scno);
 	return 0;
 }

arch/arm64/kernel/syscall.c

@@ -13,16 +13,15 @@
 #include <asm/thread_info.h>
 #include <asm/unistd.h>
 
-long compat_arm_syscall(struct pt_regs *regs);
-
+long compat_arm_syscall(struct pt_regs *regs, int scno);
 long sys_ni_syscall(void);
 
-asmlinkage long do_ni_syscall(struct pt_regs *regs)
+static long do_ni_syscall(struct pt_regs *regs, int scno)
 {
 #ifdef CONFIG_COMPAT
 	long ret;
 	if (is_compat_task()) {
-		ret = compat_arm_syscall(regs);
+		ret = compat_arm_syscall(regs, scno);
 		if (ret != -ENOSYS)
 			return ret;
 	}
@@ -47,7 +46,7 @@ static void invoke_syscall(struct pt_regs *regs, unsigned int scno,
 		syscall_fn = syscall_table[array_index_nospec(scno, sc_nr)];
 		ret = __invoke_syscall(regs, syscall_fn);
 	} else {
-		ret = do_ni_syscall(regs);
+		ret = do_ni_syscall(regs, scno);
 	}
 
 	regs->regs[0] = ret;