[PATCH v2 08/12] riscv: extend execmem_params for kprobes allocations

Mike Rapoport
2023-06-16T08:53:04Z

From: "Mike Rapoport (IBM)" <rppt@kernel.org>

RISC-V overrides kprobes::alloc_insn_range() to use the entire vmalloc area
rather than limit the allocations to the modules area.

Slightly reorder execmem_params initialization to support both 32 and 64
bit variantsi and add definition of jit area to execmem_params to support
generic kprobes::alloc_insn_page().

Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
---
arch/riscv/kernel/module.c | 16 +++++++++++++++-
arch/riscv/kernel/probes/kprobes.c | 10 ----------
2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
index ee5e04cd3f21..cca6ed4e9340 100644
--- a/arch/riscv/kernel/module.c
+++ b/arch/riscv/kernel/module.c
@@ -436,7 +436,7 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
return 0;
}

-#if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
+#ifdef CONFIG_MMU
static struct execmem_params execmem_params = {
.modules = {
.text = {
@@ -444,12 +444,26 @@ static struct execmem_params execmem_params = {
.alignment = 1,
},
},
+ .jit = {
+ .text = {
+ .pgprot = PAGE_KERNEL_READ_EXEC,
+ .alignment = 1,
+ },
+ },
};

struct execmem_params __init *execmem_arch_params(void)
{
+#ifdef CONFIG_64BIT
execmem_params.modules.text.start = MODULES_VADDR;
execmem_params.modules.text.end = MODULES_END;
+#else
+ execmem_params.modules.text.start = VMALLOC_START;
+ execmem_params.modules.text.end = VMALLOC_END;
+#endif
+
+ execmem_params.jit.text.start = VMALLOC_START;
+ execmem_params.jit.text.end = VMALLOC_END;

return &execmem_params;
}
diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c
index 2f08c14a933d..e64f2f3064eb 100644
--- a/arch/riscv/kernel/probes/kprobes.c
+++ b/arch/riscv/kernel/probes/kprobes.c
@@ -104,16 +104,6 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
return 0;
}

-#ifdef CONFIG_MMU
-void *alloc_insn_page(void)
-{
- return __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START, VMALLOC_END,
- GFP_KERNEL, PAGE_KERNEL_READ_EXEC,
- VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
- __builtin_return_address(0));
-}
-#endif
-
/* install breakpoint in text */
void __kprobes arch_arm_kprobe(struct kprobe *p)
{
--
2.35.1