6.6-stable review patch. If anyone has any objections, please let me know.
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From: Alexandre Ghiti alexghiti@rivosinc.com
[ Upstream commit 420370f3ae3d3b883813fd3051a38805160b2b9f ]
Otherwise we fall through to vmalloc_to_page() which panics since the address does not lie in the vmalloc region.
Fixes: 043cb41a85de ("riscv: introduce interfaces to patch kernel code") Signed-off-by: Alexandre Ghiti alexghiti@rivosinc.com Reviewed-by: Charlie Jenkins charlie@rivosinc.com Link: https://lore.kernel.org/r/20231214091926.203439-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/include/asm/sections.h | 1 + arch/riscv/kernel/patch.c | 11 ++++++++++- arch/riscv/kernel/vmlinux-xip.lds.S | 2 ++ arch/riscv/kernel/vmlinux.lds.S | 2 ++ 4 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h index 32336e8a17cb..a393d5035c54 100644 --- a/arch/riscv/include/asm/sections.h +++ b/arch/riscv/include/asm/sections.h @@ -13,6 +13,7 @@ extern char _start_kernel[]; extern char __init_data_begin[], __init_data_end[]; extern char __init_text_begin[], __init_text_end[]; extern char __alt_start[], __alt_end[]; +extern char __exittext_begin[], __exittext_end[];
static inline bool is_va_kernel_text(uintptr_t va) { diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c index 13ee7bf589a1..37e87fdcf6a0 100644 --- a/arch/riscv/kernel/patch.c +++ b/arch/riscv/kernel/patch.c @@ -14,6 +14,7 @@ #include <asm/fixmap.h> #include <asm/ftrace.h> #include <asm/patch.h> +#include <asm/sections.h>
struct patch_insn { void *addr; @@ -25,6 +26,14 @@ struct patch_insn { int riscv_patch_in_stop_machine = false;
#ifdef CONFIG_MMU + +static inline bool is_kernel_exittext(uintptr_t addr) +{ + return system_state < SYSTEM_RUNNING && + addr >= (uintptr_t)__exittext_begin && + addr < (uintptr_t)__exittext_end; +} + /* * The fix_to_virt(, idx) needs a const value (not a dynamic variable of * reg-a0) or BUILD_BUG_ON failed with "idx >= __end_of_fixed_addresses". @@ -35,7 +44,7 @@ static __always_inline void *patch_map(void *addr, const unsigned int fixmap) uintptr_t uintaddr = (uintptr_t) addr; struct page *page;
- if (core_kernel_text(uintaddr)) + if (core_kernel_text(uintaddr) || is_kernel_exittext(uintaddr)) page = phys_to_page(__pa_symbol(addr)); else if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) page = vmalloc_to_page(addr); diff --git a/arch/riscv/kernel/vmlinux-xip.lds.S b/arch/riscv/kernel/vmlinux-xip.lds.S index 50767647fbc6..8c3daa1b0531 100644 --- a/arch/riscv/kernel/vmlinux-xip.lds.S +++ b/arch/riscv/kernel/vmlinux-xip.lds.S @@ -29,10 +29,12 @@ SECTIONS HEAD_TEXT_SECTION INIT_TEXT_SECTION(PAGE_SIZE) /* we have to discard exit text and such at runtime, not link time */ + __exittext_begin = .; .exit.text : { EXIT_TEXT } + __exittext_end = .;
.text : { _text = .; diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S index 492dd4b8f3d6..002ca58dd998 100644 --- a/arch/riscv/kernel/vmlinux.lds.S +++ b/arch/riscv/kernel/vmlinux.lds.S @@ -69,10 +69,12 @@ SECTIONS __soc_builtin_dtb_table_end = .; } /* we have to discard exit text and such at runtime, not link time */ + __exittext_begin = .; .exit.text : { EXIT_TEXT } + __exittext_end = .;
__init_text_end = .; . = ALIGN(SECTION_ALIGN);