Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fix from Will Deacon:
- Implement a basic static call trampoline to fix CFI failures with the
generic implementation
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: Use static call trampolines when kCFI is enabled
+57
+1
arch/arm64/Kconfig
+1
arch/arm64/Kconfig
+31
arch/arm64/include/asm/static_call.h
+31
arch/arm64/include/asm/static_call.h
···
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/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _ASM_STATIC_CALL_H
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#define _ASM_STATIC_CALL_H
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#define __ARCH_DEFINE_STATIC_CALL_TRAMP(name, target) \
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asm(" .pushsection .static_call.text, \"ax\" \n" \
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" .align 4 \n" \
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" .globl " name " \n" \
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name ": \n" \
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" hint 34 /* BTI C */ \n" \
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" adrp x16, 1f \n" \
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" ldr x16, [x16, :lo12:1f] \n" \
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" br x16 \n" \
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" .type " name ", %function \n" \
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" .size " name ", . - " name " \n" \
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" .popsection \n" \
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" .pushsection .rodata, \"a\" \n" \
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" .align 3 \n" \
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"1: .quad " target " \n" \
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" .popsection \n")
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#define ARCH_DEFINE_STATIC_CALL_TRAMP(name, func) \
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__ARCH_DEFINE_STATIC_CALL_TRAMP(STATIC_CALL_TRAMP_STR(name), #func)
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#define ARCH_DEFINE_STATIC_CALL_NULL_TRAMP(name) \
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ARCH_DEFINE_STATIC_CALL_TRAMP(name, __static_call_return0)
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#define ARCH_DEFINE_STATIC_CALL_RET0_TRAMP(name) \
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ARCH_DEFINE_STATIC_CALL_TRAMP(name, __static_call_return0)
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#endif /* _ASM_STATIC_CALL_H */
+1
arch/arm64/kernel/Makefile
+1
arch/arm64/kernel/Makefile
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obj-$(CONFIG_PERF_EVENTS) += perf_regs.o perf_callchain.o
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obj-$(CONFIG_HARDLOCKUP_DETECTOR_PERF) += watchdog_hld.o
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obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
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obj-$(CONFIG_HAVE_STATIC_CALL) += static_call.o
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obj-$(CONFIG_CPU_PM) += sleep.o suspend.o
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obj-$(CONFIG_KGDB) += kgdb.o
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obj-$(CONFIG_EFI) += efi.o efi-rt-wrapper.o
+23
arch/arm64/kernel/static_call.c
+23
arch/arm64/kernel/static_call.c
···
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// SPDX-License-Identifier: GPL-2.0
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#include <linux/static_call.h>
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#include <linux/memory.h>
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#include <asm/text-patching.h>
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void arch_static_call_transform(void *site, void *tramp, void *func, bool tail)
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{
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u64 literal;
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int ret;
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if (!func)
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func = __static_call_return0;
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/* decode the instructions to discover the literal address */
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literal = ALIGN_DOWN((u64)tramp + 4, SZ_4K) +
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aarch64_insn_adrp_get_offset(le32_to_cpup(tramp + 4)) +
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8 * aarch64_insn_decode_immediate(AARCH64_INSN_IMM_12,
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le32_to_cpup(tramp + 8));
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ret = aarch64_insn_write_literal_u64((void *)literal, (u64)func);
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WARN_ON_ONCE(ret);
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}
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EXPORT_SYMBOL_GPL(arch_static_call_transform);