Merge tag 'powerpc-5.8-3' of git://git.kernel.org/pub/scm/linux/kerne…

…l/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

 - One fix for the interrupt rework we did last release which broke
   KVM-PR

 - Three commits fixing some fallout from the READ_ONCE() changes
   interacting badly with our 8xx 16K pages support, which uses a pte_t
   that is a structure of 4 actual PTEs

 - A cleanup of the 8xx pte_update() to use the newly added pmd_off()

 - A fix for a crash when handling an oops if CONFIG_DEBUG_VIRTUAL is
   enabled

 - A minor fix for the SPU syscall generation

Thanks to Aneesh Kumar K.V, Christian Zigotzky, Christophe Leroy, Mike
Rapoport, Nicholas Piggin.

* tag 'powerpc-5.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/8xx: Provide ptep_get() with 16k pages
  mm: Allow arches to provide ptep_get()
  mm/gup: Use huge_ptep_get() in gup_hugepte()
  powerpc/syscalls: Use the number when building SPU syscall table
  powerpc/8xx: use pmd_off() to access a PMD entry in pte_update()
  powerpc/64s: Fix KVM interrupt using wrong save area
  powerpc: Fix kernel crash in show_instructions() w/DEBUG_VIRTUAL

arch/powerpc/include/asm/nohash/32/pgtable.h

@@ -205,10 +205,6 @@ static inline void pmd_clear(pmd_t *pmdp)
 	*pmdp = __pmd(0);
 }
 
-/* to find an entry in a page-table-directory */
-#define pgd_index(address)	 ((address) >> PGDIR_SHIFT)
-#define pgd_offset(mm, address)	 ((mm)->pgd + pgd_index(address))
-
 /*
  * PTE updates. This function is called whenever an existing
  * valid PTE is updated. This does -not- include set_pte_at()
@@ -230,14 +226,16 @@ static inline void pmd_clear(pmd_t *pmdp)
  * For other page sizes, we have a single entry in the table.
  */
 #ifdef CONFIG_PPC_8xx
+static pmd_t *pmd_off(struct mm_struct *mm, unsigned long addr);
+
 static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, pte_t *p,
 				     unsigned long clr, unsigned long set, int huge)
 {
 	pte_basic_t *entry = &p->pte;
 	pte_basic_t old = pte_val(*p);
 	pte_basic_t new = (old & ~(pte_basic_t)clr) | set;
 	int num, i;
-	pmd_t *pmd = pmd_offset(pud_offset(p4d_offset(pgd_offset(mm, addr), addr), addr), addr);
+	pmd_t *pmd = pmd_off(mm, addr);
 
 	if (!huge)
 		num = PAGE_SIZE / SZ_4K;
@@ -286,6 +284,16 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 	return __pte(pte_update(mm, addr, ptep, ~0, 0, 0));
 }
 
+#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PPC_16K_PAGES)
+#define __HAVE_ARCH_PTEP_GET
+static inline pte_t ptep_get(pte_t *ptep)
+{
+	pte_t pte = {READ_ONCE(ptep->pte), 0, 0, 0};
+
+	return pte;
+}
+#endif
+
 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
 				      pte_t *ptep)

arch/powerpc/kernel/exceptions-64s.S

@@ -270,7 +270,7 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
 	.endif
 
-	ld	r10,PACA_EXGEN+EX_CTR(r13)
+	ld	r10,IAREA+EX_CTR(r13)
 	mtctr	r10
 BEGIN_FTR_SECTION
 	ld	r10,IAREA+EX_PPR(r13)
@@ -298,7 +298,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 
 	.if IKVM_SKIP
 89:	mtocrf	0x80,r9
-	ld	r10,PACA_EXGEN+EX_CTR(r13)
+	ld	r10,IAREA+EX_CTR(r13)
 	mtctr	r10
 	ld	r9,IAREA+EX_R9(r13)
 	ld	r10,IAREA+EX_R10(r13)

arch/powerpc/kernel/process.c

@@ -1252,29 +1252,31 @@ struct task_struct *__switch_to(struct task_struct *prev,
 static void show_instructions(struct pt_regs *regs)
 {
 	int i;
+	unsigned long nip = regs->nip;
 	unsigned long pc = regs->nip - (NR_INSN_TO_PRINT * 3 / 4 * sizeof(int));
 
 	printk("Instruction dump:");
 
+	/*
+	 * If we were executing with the MMU off for instructions, adjust pc
+	 * rather than printing XXXXXXXX.
+	 */
+	if (!IS_ENABLED(CONFIG_BOOKE) && !(regs->msr & MSR_IR)) {
+		pc = (unsigned long)phys_to_virt(pc);
+		nip = (unsigned long)phys_to_virt(regs->nip);
+	}
+
 	for (i = 0; i < NR_INSN_TO_PRINT; i++) {
 		int instr;
 
 		if (!(i % 8))
 			pr_cont("\n");
 
-#if !defined(CONFIG_BOOKE)
-		/* If executing with the IMMU off, adjust pc rather
-		 * than print XXXXXXXX.
-		 */
-		if (!(regs->msr & MSR_IR))
-			pc = (unsigned long)phys_to_virt(pc);
-#endif
-
 		if (!__kernel_text_address(pc) ||
 		    get_kernel_nofault(instr, (const void *)pc)) {
 			pr_cont("XXXXXXXX ");
 		} else {
-			if (regs->nip == pc)
+			if (nip == pc)
 				pr_cont("<%08x> ", instr);
 			else
 				pr_cont("%08x ", instr);

arch/powerpc/platforms/cell/spu_callbacks.c

@@ -35,7 +35,7 @@
  */
 
 static void *spu_syscall_table[] = {
-#define __SYSCALL(nr, entry)	entry,
+#define __SYSCALL(nr, entry) [nr] = entry,
 #include <asm/syscall_table_spu.h>
 #undef __SYSCALL
 };

include/asm-generic/hugetlb.h

@@ -122,7 +122,7 @@ static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 #ifndef __HAVE_ARCH_HUGE_PTEP_GET
 static inline pte_t huge_ptep_get(pte_t *ptep)
 {
-	return READ_ONCE(*ptep);
+	return ptep_get(ptep);
 }
 #endif
 

include/linux/pgtable.h

@@ -249,6 +249,13 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
 }
 #endif
 
+#ifndef __HAVE_ARCH_PTEP_GET
+static inline pte_t ptep_get(pte_t *ptep)
+{
+	return READ_ONCE(*ptep);
+}
+#endif
+
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 #ifndef __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,

mm/gup.c

@@ -2196,7 +2196,7 @@ static inline pte_t gup_get_pte(pte_t *ptep)
  */
 static inline pte_t gup_get_pte(pte_t *ptep)
 {
-	return READ_ONCE(*ptep);
+	return ptep_get(ptep);
 }
 #endif /* CONFIG_GUP_GET_PTE_LOW_HIGH */
 
@@ -2425,7 +2425,7 @@ static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
 	if (pte_end < end)
 		end = pte_end;
 
-	pte = READ_ONCE(*ptep);
+	pte = huge_ptep_get(ptep);
 
 	if (!pte_access_permitted(pte, flags & FOLL_WRITE))
 		return 0;