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

Pull arm64 updates from Catalin Marinas:

 - Support for running Linux in a protected VM under the Arm
   Confidential Compute Architecture (CCA)

 - Guarded Control Stack user-space support. Current patches follow the
   x86 ABI of implicitly creating a shadow stack on clone(). Subsequent
   patches (already on the list) will add support for clone3() allowing
   finer-grained control of the shadow stack size and placement from
   libc

 - AT_HWCAP3 support (not running out of HWCAP2 bits yet but we are
   getting close with the upcoming dpISA support)

 - Other arch features:

     - In-kernel use of the memcpy instructions, FEAT_MOPS (previously
       only exposed to user; uaccess support not merged yet)

     - MTE: hugetlbfs support and the corresponding kselftests

     - Optimise CRC32 using the PMULL instructions

     - Support for FEAT_HAFT enabling ARCH_HAS_NONLEAF_PMD_YOUNG

     - Optimise the kernel TLB flushing to use the range operations

     - POE/pkey (permission overlays): further cleanups after bringing
       the signal handler in line with the x86 behaviour for 6.12

 - arm64 perf updates:

     - Support for the NXP i.MX91 PMU in the existing IMX driver

     - Support for Ampere SoCs in the Designware PCIe PMU driver

     - Support for Marvell's 'PEM' PCIe PMU present in the 'Odyssey' SoC

     - Support for Samsung's 'Mongoose' CPU PMU

     - Support for PMUv3.9 finer-grained userspace counter access
       control

     - Switch back to platform_driver::remove() now that it returns
       'void'

     - Add some missing events for the CXL PMU driver

 - Miscellaneous arm64 fixes/cleanups:

     - Page table accessors cleanup: type updates, drop unused macros,
       reorganise arch_make_huge_pte() and clean up pte_mkcont(), sanity
       check addresses before runtime P4D/PUD folding

     - Command line override for ID_AA64MMFR0_EL1.ECV (advertising the
       FEAT_ECV for the generic timers) allowing Linux to boot with
       firmware deployments that don't set SCTLR_EL3.ECVEn

     - ACPI/arm64: tighten the check for the array of platform timer
       structures and adjust the error handling procedure in
       gtdt_parse_timer_block()

     - Optimise the cache flush for the uprobes xol slot (skip if no
       change) and other uprobes/kprobes cleanups

     - Fix the context switching of tpidrro_el0 when kpti is enabled

     - Dynamic shadow call stack fixes

     - Sysreg updates

     - Various arm64 kselftest improvements

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (168 commits)
  arm64: tls: Fix context-switching of tpidrro_el0 when kpti is enabled
  kselftest/arm64: Try harder to generate different keys during PAC tests
  kselftest/arm64: Don't leak pipe fds in pac.exec_sign_all()
  arm64/ptrace: Clarify documentation of VL configuration via ptrace
  kselftest/arm64: Corrupt P0 in the irritator when testing SSVE
  acpi/arm64: remove unnecessary cast
  arm64/mm: Change protval as 'pteval_t' in map_range()
  kselftest/arm64: Fix missing printf() argument in gcs/gcs-stress.c
  kselftest/arm64: Add FPMR coverage to fp-ptrace
  kselftest/arm64: Expand the set of ZA writes fp-ptrace does
  kselftets/arm64: Use flag bits for features in fp-ptrace assembler code
  kselftest/arm64: Enable build of PAC tests with LLVM=1
  kselftest/arm64: Check that SVCR is 0 in signal handlers
  selftests/mm: Fix unused function warning for aarch64_write_signal_pkey()
  kselftest/arm64: Fix printf() compiler warnings in the arm64 syscall-abi.c tests
  kselftest/arm64: Fix printf() warning in the arm64 MTE prctl() test
  kselftest/arm64: Fix printf() compiler warnings in the arm64 fp tests
  kselftest/arm64: Fix build with stricter assemblers
  arm64/scs: Drop unused prototype __pi_scs_patch_vmlinux()
  arm64/scs: Deal with 64-bit relative offsets in FDE frames
  ...

1 files changed, 42 insertions, 15 deletions

diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index 1438424f0064..1bf1a3b16e88 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -185,6 +185,13 @@ struct thread_struct {
 	u64			svcr;
 	u64			tpidr2_el0;
 	u64			por_el0;
+#ifdef CONFIG_ARM64_GCS
+	unsigned int		gcs_el0_mode;
+	unsigned int		gcs_el0_locked;
+	u64			gcspr_el0;
+	u64			gcs_base;
+	u64			gcs_size;
+#endif
 };
 
 static inline unsigned int thread_get_vl(struct thread_struct *thread,
@@ -285,22 +292,44 @@ void tls_preserve_current_state(void);
 	.fpsimd_cpu = NR_CPUS,			\
 }
 
-static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)
+static inline void start_thread_common(struct pt_regs *regs, unsigned long pc,
+				       unsigned long pstate)
 {
-	s32 previous_syscall = regs->syscallno;
-	memset(regs, 0, sizeof(*regs));
-	regs->syscallno = previous_syscall;
-	regs->pc = pc;
+	/*
+	 * Ensure all GPRs are zeroed, and initialize PC + PSTATE.
+	 * The SP (or compat SP) will be initialized later.
+	 */
+	regs->user_regs = (struct user_pt_regs) {
+		.pc = pc,
+		.pstate = pstate,
+	};
 
+	/*
+	 * To allow the syscalls:sys_exit_execve tracepoint we need to preserve
+	 * syscallno, but do not need orig_x0 or the original GPRs.
+	 */
+	regs->orig_x0 = 0;
+
+	/*
+	 * An exec from a kernel thread won't have an existing PMR value.
+	 */
 	if (system_uses_irq_prio_masking())
-		regs->pmr_save = GIC_PRIO_IRQON;
+		regs->pmr = GIC_PRIO_IRQON;
+
+	/*
+	 * The pt_regs::stackframe field must remain valid throughout this
+	 * function as a stacktrace can be taken at any time. Any user or
+	 * kernel task should have a valid final frame.
+	 */
+	WARN_ON_ONCE(regs->stackframe.record.fp != 0);
+	WARN_ON_ONCE(regs->stackframe.record.lr != 0);
+	WARN_ON_ONCE(regs->stackframe.type != FRAME_META_TYPE_FINAL);
 }
 
 static inline void start_thread(struct pt_regs *regs, unsigned long pc,
 				unsigned long sp)
 {
-	start_thread_common(regs, pc);
-	regs->pstate = PSR_MODE_EL0t;
+	start_thread_common(regs, pc, PSR_MODE_EL0t);
 	spectre_v4_enable_task_mitigation(current);
 	regs->sp = sp;
 }
@@ -309,15 +338,13 @@ static inline void start_thread(struct pt_regs *regs, unsigned long pc,
 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
 				       unsigned long sp)
 {
-	start_thread_common(regs, pc);
-	regs->pstate = PSR_AA32_MODE_USR;
+	unsigned long pstate = PSR_AA32_MODE_USR;
 	if (pc & 1)
-		regs->pstate |= PSR_AA32_T_BIT;
-
-#ifdef __AARCH64EB__
-	regs->pstate |= PSR_AA32_E_BIT;
-#endif
+		pstate |= PSR_AA32_T_BIT;
+	if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+		pstate |= PSR_AA32_E_BIT;
 
+	start_thread_common(regs, pc, pstate);
 	spectre_v4_enable_task_mitigation(current);
 	regs->compat_sp = sp;
 }