[PATCH 3/4] powerpc/64s: Allow double call of kernel_[un]map_linear_page()
From: Jordan Niethe <hidden>
Date: 2021-05-17 06:18:59
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
From: Christophe Leroy <redacted> If the page is already mapped resp. already unmapped, bail out. Signed-off-by: Christophe Leroy <redacted> Signed-off-by: Jordan Niethe <redacted> --- arch/powerpc/mm/book3s64/hash_utils.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c
index d74482cce064..fe5cf1cf4dd5 100644
--- a/arch/powerpc/mm/book3s64/hash_utils.c
+++ b/arch/powerpc/mm/book3s64/hash_utils.c@@ -1953,6 +1953,9 @@ static void kernel_map_linear_page(unsigned long vaddr, unsigned long lmi) if (!vsid) return; + if (linear_map_hash_slots[lmi] & 0x80) + return; + ret = hpte_insert_repeating(hash, vpn, __pa(vaddr), mode, HPTE_V_BOLTED, mmu_linear_psize, mmu_kernel_ssize);
@@ -1972,7 +1975,10 @@ static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi) hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize); spin_lock(&linear_map_hash_lock); - BUG_ON(!(linear_map_hash_slots[lmi] & 0x80)); + if (!(linear_map_hash_slots[lmi] & 0x80)) { + spin_unlock(&linear_map_hash_lock); + return; + } hidx = linear_map_hash_slots[lmi] & 0x7f; linear_map_hash_slots[lmi] = 0; spin_unlock(&linear_map_hash_lock);
--
2.25.1