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, 43 insertions, 31 deletions

diff --git a/arch/arm64/include/asm/stacktrace/common.h b/arch/arm64/include/asm/stacktrace/common.h
index f63dc654e545..821a8fdd31af 100644
--- a/arch/arm64/include/asm/stacktrace/common.h
+++ b/arch/arm64/include/asm/stacktrace/common.h
@@ -60,13 +60,27 @@ static inline void unwind_init_common(struct unwind_state *state)
 	state->stack = stackinfo_get_unknown();
 }
 
-static struct stack_info *unwind_find_next_stack(const struct unwind_state *state,
-						 unsigned long sp,
-						 unsigned long size)
+/**
+ * unwind_find_stack() - Find the accessible stack which entirely contains an
+ * object.
+ *
+ * @state: the current unwind state.
+ * @sp:    the base address of the object.
+ * @size:  the size of the object.
+ *
+ * Return: a pointer to the relevant stack_info if found; NULL otherwise.
+ */
+static struct stack_info *unwind_find_stack(struct unwind_state *state,
+					    unsigned long sp,
+					    unsigned long size)
 {
-	for (int i = 0; i < state->nr_stacks; i++) {
-		struct stack_info *info = &state->stacks[i];
+	struct stack_info *info = &state->stack;
 
+	if (stackinfo_on_stack(info, sp, size))
+		return info;
+
+	for (int i = 0; i < state->nr_stacks; i++) {
+		info = &state->stacks[i];
 		if (stackinfo_on_stack(info, sp, size))
 			return info;
 	}
@@ -75,36 +89,31 @@ static struct stack_info *unwind_find_next_stack(const struct unwind_state *stat
 }
 
 /**
- * unwind_consume_stack() - Check if an object is on an accessible stack,
- * updating stack boundaries so that future unwind steps cannot consume this
- * object again.
+ * unwind_consume_stack() - Update stack boundaries so that future unwind steps
+ * cannot consume this object again.
  *
  * @state: the current unwind state.
+ * @info:  the stack_info of the stack containing the object.
  * @sp:    the base address of the object.
  * @size:  the size of the object.
  *
  * Return: 0 upon success, an error code otherwise.
  */
-static inline int unwind_consume_stack(struct unwind_state *state,
-				       unsigned long sp,
-				       unsigned long size)
+static inline void unwind_consume_stack(struct unwind_state *state,
+					struct stack_info *info,
+					unsigned long sp,
+					unsigned long size)
 {
-	struct stack_info *next;
-
-	if (stackinfo_on_stack(&state->stack, sp, size))
-		goto found;
-
-	next = unwind_find_next_stack(state, sp, size);
-	if (!next)
-		return -EINVAL;
+	struct stack_info tmp;
 
 	/*
 	 * Stack transitions are strictly one-way, and once we've
 	 * transitioned from one stack to another, it's never valid to
 	 * unwind back to the old stack.
 	 *
-	 * Remove the current stack from the list of stacks so that it cannot
-	 * be found on a subsequent transition.
+	 * Destroy the old stack info so that it cannot be found upon a
+	 * subsequent transition. If the stack has not changed, we'll
+	 * immediately restore the current stack info.
 	 *
 	 * Note that stacks can nest in several valid orders, e.g.
 	 *
@@ -115,16 +124,15 @@ static inline int unwind_consume_stack(struct unwind_state *state,
 	 * ... so we do not check the specific order of stack
 	 * transitions.
 	 */
-	state->stack = *next;
-	*next = stackinfo_get_unknown();
+	tmp = *info;
+	*info = stackinfo_get_unknown();
+	state->stack = tmp;
 
-found:
 	/*
 	 * Future unwind steps can only consume stack above this frame record.
 	 * Update the current stack to start immediately above it.
 	 */
 	state->stack.low = sp + size;
-	return 0;
 }
 
 /**
@@ -137,21 +145,25 @@ found:
 static inline int
 unwind_next_frame_record(struct unwind_state *state)
 {
+	struct stack_info *info;
+	struct frame_record *record;
 	unsigned long fp = state->fp;
-	int err;
 
 	if (fp & 0x7)
 		return -EINVAL;
 
-	err = unwind_consume_stack(state, fp, 16);
-	if (err)
-		return err;
+	info = unwind_find_stack(state, fp, sizeof(*record));
+	if (!info)
+		return -EINVAL;
+
+	unwind_consume_stack(state, info, fp, sizeof(*record));
 
 	/*
 	 * Record this frame record's values.
 	 */
-	state->fp = READ_ONCE(*(unsigned long *)(fp));
-	state->pc = READ_ONCE(*(unsigned long *)(fp + 8));
+	record = (struct frame_record *)fp;
+	state->fp = READ_ONCE(record->fp);
+	state->pc = READ_ONCE(record->lr);
 
 	return 0;
 }