From 9d05c20b0ac97a688f6f6747da45b4d1e287b806 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Mon, 14 Nov 2022 14:40:42 +0000 Subject: [PATCH] arm64: make is_ttbrX_addr() noinstr-safe [ Upstream commit d8c1d798a2e5091128c391c6dadcc9be334af3f5 ] We use is_ttbr0_addr() in noinstr code, but as it's only marked as inline, it's theoretically possible for the compiler to place it out-of-line and instrument it, which would be problematic. Mark is_ttbr0_addr() as __always_inline such that that can safely be used from noinstr code. For consistency, do the same to is_ttbr1_addr(). Note that while is_ttbr1_addr() calls arch_kasan_reset_tag(), this is a macro (and its callees are either macros or __always_inline), so there is not a risk of transient instrumentation. Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: Will Deacon Link: https://lore.kernel.org/r/20221114144042.3001140-1-mark.rutland@arm.com Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- arch/arm64/include/asm/processor.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index d9bf3d1..7364530 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -240,13 +240,13 @@ static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc, } #endif -static inline bool is_ttbr0_addr(unsigned long addr) +static __always_inline bool is_ttbr0_addr(unsigned long addr) { /* entry assembly clears tags for TTBR0 addrs */ return addr < TASK_SIZE; } -static inline bool is_ttbr1_addr(unsigned long addr) +static __always_inline bool is_ttbr1_addr(unsigned long addr) { /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */ return arch_kasan_reset_tag(addr) >= PAGE_OFFSET; -- 2.7.4