Merge tag 'parisc-for-6.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux

Pull parisc fix from Helge Deller:
 "On parisc we have suffered since years from random segfaults which
  seem to have been triggered due to cache inconsistencies. Those
  segfaults happened more often on machines with PA8800 and PA8900 CPUs,
  which have much bigger caches than the earlier machines.

  Dave Anglin has worked over the last few weeks to fix this bug. His
  patch has been successfully tested by various people on various
  machines and with various kernels (6.6, 6.8 and 6.9), and the debian
  buildd servers haven't shown a single random segfault with this patch.

  Since the cache handling has been reworked, the patch is slightly
  bigger than I would like in this stage, but the greatly improved
  stability IMHO justifies the inclusion now"

* tag 'parisc-for-6.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Try to fix random segmentation faults in package builds

Author: torvalds

arch/parisc/include/asm/cacheflush.h

@@ -31,18 +31,17 @@ void flush_cache_all_local(void);
 void flush_cache_all(void);
 void flush_cache_mm(struct mm_struct *mm);
 
-void flush_kernel_dcache_page_addr(const void *addr);
-
 #define flush_kernel_dcache_range(start,size) \
 	flush_kernel_dcache_range_asm((start), (start)+(size));
 
+/* The only way to flush a vmap range is to flush whole cache */
 #define ARCH_IMPLEMENTS_FLUSH_KERNEL_VMAP_RANGE 1
 void flush_kernel_vmap_range(void *vaddr, int size);
 void invalidate_kernel_vmap_range(void *vaddr, int size);
 
-#define flush_cache_vmap(start, end)		flush_cache_all()
+void flush_cache_vmap(unsigned long start, unsigned long end);
 #define flush_cache_vmap_early(start, end)	do { } while (0)
-#define flush_cache_vunmap(start, end)		flush_cache_all()
+void flush_cache_vunmap(unsigned long start, unsigned long end);
 
 void flush_dcache_folio(struct folio *folio);
 #define flush_dcache_folio flush_dcache_folio
@@ -77,17 +76,11 @@ void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
 void flush_cache_range(struct vm_area_struct *vma,
 		unsigned long start, unsigned long end);
 
-/* defined in pacache.S exported in cache.c used by flush_anon_page */
-void flush_dcache_page_asm(unsigned long phys_addr, unsigned long vaddr);
-
 #define ARCH_HAS_FLUSH_ANON_PAGE
 void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr);
 
 #define ARCH_HAS_FLUSH_ON_KUNMAP
-static inline void kunmap_flush_on_unmap(const void *addr)
-{
-	flush_kernel_dcache_page_addr(addr);
-}
+void kunmap_flush_on_unmap(const void *addr);
 
 #endif /* _PARISC_CACHEFLUSH_H */
 

arch/parisc/include/asm/pgtable.h

@@ -448,32 +448,28 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
 	return pte;
 }
 
+static inline pte_t ptep_get(pte_t *ptep)
+{
+	return READ_ONCE(*ptep);
+}
+#define ptep_get ptep_get
+
 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
 {
 	pte_t pte;
 
-	if (!pte_young(*ptep))
-		return 0;
-
-	pte = *ptep;
+	pte = ptep_get(ptep);
 	if (!pte_young(pte)) {
 		return 0;
 	}
 	set_pte(ptep, pte_mkold(pte));
 	return 1;
 }
 
-struct mm_struct;
-static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
-{
-	pte_t old_pte;
-
-	old_pte = *ptep;
-	set_pte(ptep, __pte(0));
-
-	return old_pte;
-}
+int ptep_clear_flush_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep);
+pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep);
 
+struct mm_struct;
 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 {
 	set_pte(ptep, pte_wrprotect(*ptep));
@@ -511,7 +507,8 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
 
 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
-#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
+#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
+#define __HAVE_ARCH_PTEP_CLEAR_FLUSH
 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
 #define __HAVE_ARCH_PTE_SAME