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-rw-r--r--arch/riscv/include/asm/cacheflush.h25
-rw-r--r--arch/riscv/include/asm/kfence.h7
-rw-r--r--arch/riscv/kernel/entry.S6
3 files changed, 23 insertions, 15 deletions
diff --git a/arch/riscv/include/asm/cacheflush.h b/arch/riscv/include/asm/cacheflush.h
index 0092513c3376..b1a2ac665792 100644
--- a/arch/riscv/include/asm/cacheflush.h
+++ b/arch/riscv/include/asm/cacheflush.h
@@ -43,20 +43,23 @@ do { \
#ifdef CONFIG_64BIT
extern u64 new_vmalloc[NR_CPUS / sizeof(u64) + 1];
extern char _end[];
+static inline void mark_new_valid_map(void)
+{
+ int i;
+
+ /*
+ * We don't care if concurrently a cpu resets this value since
+ * the only place this can happen is in handle_exception() where
+ * an sfence.vma is emitted.
+ */
+ for (i = 0; i < ARRAY_SIZE(new_vmalloc); ++i)
+ new_vmalloc[i] = -1ULL;
+}
#define flush_cache_vmap flush_cache_vmap
static inline void flush_cache_vmap(unsigned long start, unsigned long end)
{
- if (is_vmalloc_or_module_addr((void *)start)) {
- int i;
-
- /*
- * We don't care if concurrently a cpu resets this value since
- * the only place this can happen is in handle_exception() where
- * an sfence.vma is emitted.
- */
- for (i = 0; i < ARRAY_SIZE(new_vmalloc); ++i)
- new_vmalloc[i] = -1ULL;
- }
+ if (is_vmalloc_or_module_addr((void *)start))
+ mark_new_valid_map();
}
#define flush_cache_vmap_early(start, end) local_flush_tlb_kernel_range(start, end)
#endif
diff --git a/arch/riscv/include/asm/kfence.h b/arch/riscv/include/asm/kfence.h
index d08bf7fb3aee..29cb3a6ee113 100644
--- a/arch/riscv/include/asm/kfence.h
+++ b/arch/riscv/include/asm/kfence.h
@@ -6,6 +6,7 @@
#include <linux/kfence.h>
#include <linux/pfn.h>
#include <asm-generic/pgalloc.h>
+#include <asm/cacheflush.h>
#include <asm/pgtable.h>
static inline bool arch_kfence_init_pool(void)
@@ -17,10 +18,12 @@ static inline bool kfence_protect_page(unsigned long addr, bool protect)
{
pte_t *pte = virt_to_kpte(addr);
- if (protect)
+ if (protect) {
set_pte(pte, __pte(pte_val(ptep_get(pte)) & ~_PAGE_PRESENT));
- else
+ } else {
set_pte(pte, __pte(pte_val(ptep_get(pte)) | _PAGE_PRESENT));
+ mark_new_valid_map();
+ }
preempt_disable();
local_flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index d011fb51c59a..6c14ed7a5613 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -136,8 +136,10 @@ SYM_CODE_START(handle_exception)
#ifdef CONFIG_64BIT
/*
- * The RISC-V kernel does not eagerly emit a sfence.vma after each
- * new vmalloc mapping, which may result in exceptions:
+ * The RISC-V kernel does not flush TLBs on all CPUS after each new
+ * vmalloc mapping or kfence_unprotect(), which may result in
+ * exceptions:
+ *
* - if the uarch caches invalid entries, the new mapping would not be
* observed by the page table walker and an invalidation is needed.
* - if the uarch does not cache invalid entries, a reordered access