Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

Pull ARM updates from Russell King:

 - Rejig task/thread info to place thread info in task struct

 - Amba bus cleanups (removing unused functions)

 - Handle Amba device probe without IRQ domains

 - Parse linux,usable-memory-range in decompressor

 - Mark OCRAM as read-only after initialisation

 - Refactor page fault handling

 - Fix PXN handling with LPAE kernels

 - Warning and build fixes from Arnd

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (32 commits)
  ARM: 9151/1: Thumb2: avoid __builtin_thread_pointer() on Clang
  ARM: 9150/1: Fix PID_IN_CONTEXTIDR regression when THREAD_INFO_IN_TASK=y
  ARM: 9147/1: add printf format attribute to early_print()
  ARM: 9146/1: RiscPC needs older gcc version
  ARM: 9145/1: patch: fix BE32 compilation
  ARM: 9144/1: forbid ftrace with clang and thumb2_kernel
  ARM: 9143/1: add CONFIG_PHYS_OFFSET default values
  ARM: 9142/1: kasan: work around LPAE build warning
  ARM: 9140/1: allow compile-testing without machine record
  ARM: 9137/1: disallow CONFIG_THUMB with ARMv4
  ARM: 9136/1: ARMv7-M uses BE-8, not BE-32
  ARM: 9135/1: kprobes: address gcc -Wempty-body warning
  ARM: 9101/1: sa1100/assabet: convert LEDs to gpiod APIs
  ARM: 9131/1: mm: Fix PXN process with LPAE feature
  ARM: 9130/1: mm: Provide die_kernel_fault() helper
  ARM: 9126/1: mm: Kill page table base print in show_pte()
  ARM: 9127/1: mm: Cleanup access_error()
  ARM: 9129/1: mm: Kill task_struct argument for __do_page_fault()
  ARM: 9128/1: mm: Refactor the __do_page_fault()
  ARM: imx6: mark OCRAM mapping read-only
  ...

1 files changed, 55 insertions, 0 deletions

diff --git a/arch/arm/include/asm/current.h b/arch/arm/include/asm/current.h
new file mode 100644
index 000000000000..6bf0aad672c3
--- /dev/null
+++ b/arch/arm/include/asm/current.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2021 Keith Packard <keithp@keithp.com>
+ * Copyright (c) 2021 Google, LLC <ardb@kernel.org>
+ */
+
+#ifndef _ASM_ARM_CURRENT_H
+#define _ASM_ARM_CURRENT_H
+
+#ifndef __ASSEMBLY__
+
+struct task_struct;
+
+static inline void set_current(struct task_struct *cur)
+{
+	if (!IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO))
+		return;
+
+	/* Set TPIDRURO */
+	asm("mcr p15, 0, %0, c13, c0, 3" :: "r"(cur) : "memory");
+}
+
+#ifdef CONFIG_CURRENT_POINTER_IN_TPIDRURO
+
+static inline struct task_struct *get_current(void)
+{
+	struct task_struct *cur;
+
+#if __has_builtin(__builtin_thread_pointer) && \
+    !(defined(CONFIG_THUMB2_KERNEL) && \
+      defined(CONFIG_CC_IS_CLANG) && CONFIG_CLANG_VERSION < 130001)
+	/*
+	 * Use the __builtin helper when available - this results in better
+	 * code, especially when using GCC in combination with the per-task
+	 * stack protector, as the compiler will recognize that it needs to
+	 * load the TLS register only once in every function.
+	 *
+	 * Clang < 13.0.1 gets this wrong for Thumb2 builds:
+	 * https://github.com/ClangBuiltLinux/linux/issues/1485
+	 */
+	cur = __builtin_thread_pointer();
+#else
+	asm("mrc p15, 0, %0, c13, c0, 3" : "=r"(cur));
+#endif
+	return cur;
+}
+
+#define current get_current()
+#else
+#include <asm-generic/current.h>
+#endif /* CONFIG_CURRENT_POINTER_IN_TPIDRURO */
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_ARM_CURRENT_H */