powerpc fixes for 5.10 #3

Fix miscompilation with GCC 4.9 by using asm_goto_volatile for put_user().
 
 A fix for an RCU splat at boot caused by a recent lockdep change.
 
 A fix for a possible deadlock in our EEH debugfs code.
 
 Several fixes for handling of _PAGE_ACCESSED on 32-bit platforms.
 
 A build fix when CONFIG_NUMA=n.
 
 Thanks to:
   Andreas Schwab,
   Christophe Leroy,
   Oliver O'Halloran,
   Qian Cai,
   Scott Cheloha.
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Merge tag 'powerpc-5.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

 - fix miscompilation with GCC 4.9 by using asm_goto_volatile for put_user()

 - fix for an RCU splat at boot caused by a recent lockdep change

 - fix for a possible deadlock in our EEH debugfs code

 - several fixes for handling of _PAGE_ACCESSED on 32-bit platforms

 - build fix when CONFIG_NUMA=n

Thanks to Andreas Schwab, Christophe Leroy, Oliver O'Halloran, Qian Cai,
and Scott Cheloha.

* tag 'powerpc-5.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/numa: Fix build when CONFIG_NUMA=n
  powerpc/8xx: Manage _PAGE_ACCESSED through APG bits in L1 entry
  powerpc/8xx: Always fault when _PAGE_ACCESSED is not set
  powerpc/40x: Always fault when _PAGE_ACCESSED is not set
  powerpc/603: Always fault when _PAGE_ACCESSED is not set
  powerpc: Use asm_goto_volatile for put_user()
  powerpc/smp: Call rcu_cpu_starting() earlier
  powerpc/eeh_cache: Fix a possible debugfs deadlock

arch/powerpc/include/asm/nohash/32/kup-8xx.h

@@ -63,7 +63,7 @@ static inline void restore_user_access(unsigned long flags)
 static inline bool
 bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
 {
-	return WARN(!((regs->kuap ^ MD_APG_KUAP) & 0xf0000000),
+	return WARN(!((regs->kuap ^ MD_APG_KUAP) & 0xff000000),
 		    "Bug: fault blocked by AP register !");
 }
 

arch/powerpc/include/asm/nohash/32/mmu-8xx.h

@@ -33,19 +33,18 @@
  * respectively NA for All or X for Supervisor and no access for User.
  * Then we use the APG to say whether accesses are according to Page rules or
  * "all Supervisor" rules (Access to all)
- * Therefore, we define 2 APG groups. lsb is _PMD_USER
+ * _PAGE_ACCESSED is also managed via APG. When _PAGE_ACCESSED is not set, say
- * 0 => Kernel => 01 (all accesses performed according to page definition)
+ * "all User" rules, that will lead to NA for all.
- * 1 => User => 00 (all accesses performed as supervisor iaw page definition)
+ * Therefore, we define 4 APG groups. lsb is _PAGE_ACCESSED
- * 2-15 => Not Used
+ * 0 => Kernel => 11 (all accesses performed according as user iaw page definition)
+ * 1 => Kernel+Accessed => 01 (all accesses performed according to page definition)
+ * 2 => User => 11 (all accesses performed according as user iaw page definition)
+ * 3 => User+Accessed => 00 (all accesses performed as supervisor iaw page definition) for INIT
+ *                    => 10 (all accesses performed according to swaped page definition) for KUEP
+ * 4-15 => Not Used
  */
-#define MI_APG_INIT	0x40000000
+#define MI_APG_INIT	0xdc000000
-
+#define MI_APG_KUEP	0xde000000
-/*
- * 0 => Kernel => 01 (all accesses performed according to page definition)
- * 1 => User => 10 (all accesses performed according to swaped page definition)
- * 2-15 => Not Used
- */
-#define MI_APG_KUEP	0x60000000
 
 /* The effective page number register.  When read, contains the information
  * about the last instruction TLB miss.  When MI_RPN is written, bits in
@@ -106,25 +105,9 @@
 #define MD_Ks		0x80000000	/* Should not be set */
 #define MD_Kp		0x40000000	/* Should always be set */
 
-/*
+/* See explanation above at the definition of MI_APG_INIT */
- * All pages' PP data bits are set to either 000 or 011 or 001, which means
+#define MD_APG_INIT	0xdc000000
- * respectively RW for Supervisor and no access for User, or RO for
+#define MD_APG_KUAP	0xde000000
- * Supervisor and no access for user and NA for ALL.
- * Then we use the APG to say whether accesses are according to Page rules or
- * "all Supervisor" rules (Access to all)
- * Therefore, we define 2 APG groups. lsb is _PMD_USER
- * 0 => Kernel => 01 (all accesses performed according to page definition)
- * 1 => User => 00 (all accesses performed as supervisor iaw page definition)
- * 2-15 => Not Used
- */
-#define MD_APG_INIT	0x40000000
-
-/*
- * 0 => No user => 01 (all accesses performed according to page definition)
- * 1 => User => 10 (all accesses performed according to swaped page definition)
- * 2-15 => Not Used
- */
-#define MD_APG_KUAP	0x60000000
 
 /* The effective page number register.  When read, contains the information
  * about the last instruction TLB miss.  When MD_RPN is written, bits in

arch/powerpc/include/asm/nohash/32/pte-8xx.h

@@ -39,9 +39,9 @@
  * into the TLB.
  */
 #define _PAGE_GUARDED	0x0010	/* Copied to L1 G entry in DTLB */
-#define _PAGE_SPECIAL	0x0020	/* SW entry */
+#define _PAGE_ACCESSED	0x0020	/* Copied to L1 APG 1 entry in I/DTLB */
 #define _PAGE_EXEC	0x0040	/* Copied to PP (bit 21) in ITLB */
-#define _PAGE_ACCESSED	0x0080	/* software: page referenced */
+#define _PAGE_SPECIAL	0x0080	/* SW entry */
 
 #define _PAGE_NA	0x0200	/* Supervisor NA, User no access */
 #define _PAGE_RO	0x0600	/* Supervisor RO, User no access */
@@ -59,11 +59,12 @@
 
 #define _PMD_PRESENT	0x0001
 #define _PMD_PRESENT_MASK	_PMD_PRESENT
-#define _PMD_BAD	0x0fd0
+#define _PMD_BAD	0x0f90
 #define _PMD_PAGE_MASK	0x000c
 #define _PMD_PAGE_8M	0x000c
 #define _PMD_PAGE_512K	0x0004
-#define _PMD_USER	0x0020	/* APG 1 */
+#define _PMD_ACCESSED	0x0020	/* APG 1 */
+#define _PMD_USER	0x0040	/* APG 2 */
 
 #define _PTE_NONE_MASK	0
 

arch/powerpc/include/asm/topology.h

@@ -6,6 +6,7 @@
 
 struct device;
 struct device_node;
+struct drmem_lmb;
 
 #ifdef CONFIG_NUMA
 
@@ -61,6 +62,9 @@ static inline int early_cpu_to_node(int cpu)
 	 */
 	return (nid < 0) ? 0 : nid;
 }
+
+int of_drconf_to_nid_single(struct drmem_lmb *lmb);
+
 #else
 
 static inline int early_cpu_to_node(int cpu) { return 0; }
@@ -84,10 +88,12 @@ static inline int cpu_distance(__be32 *cpu1_assoc, __be32 *cpu2_assoc)
 	return 0;
 }
 
-#endif /* CONFIG_NUMA */
+static inline int of_drconf_to_nid_single(struct drmem_lmb *lmb)
+{
+	return first_online_node;
+}
 
-struct drmem_lmb;
+#endif /* CONFIG_NUMA */
-int of_drconf_to_nid_single(struct drmem_lmb *lmb);
 
 #if defined(CONFIG_NUMA) && defined(CONFIG_PPC_SPLPAR)
 extern int find_and_online_cpu_nid(int cpu);

arch/powerpc/include/asm/uaccess.h

@@ -178,7 +178,7 @@ do {								\
  * are no aliasing issues.
  */
 #define __put_user_asm_goto(x, addr, label, op)			\
-	asm volatile goto(					\
+	asm_volatile_goto(					\
 		"1:	" op "%U1%X1 %0,%1	# put_user\n"	\
 		EX_TABLE(1b, %l2)				\
 		:						\
@@ -191,7 +191,7 @@ do {								\
 	__put_user_asm_goto(x, ptr, label, "std")
 #else /* __powerpc64__ */
 #define __put_user_asm2_goto(x, addr, label)			\
-	asm volatile goto(					\
+	asm_volatile_goto(					\
 		"1:	stw%X1 %0, %1\n"			\
 		"2:	stw%X1 %L0, %L1\n"			\
 		EX_TABLE(1b, %l2)				\

arch/powerpc/kernel/eeh_cache.c

@@ -264,8 +264,9 @@ static int eeh_addr_cache_show(struct seq_file *s, void *v)
 {
 	struct pci_io_addr_range *piar;
 	struct rb_node *n;
+	unsigned long flags;
 
-	spin_lock(&pci_io_addr_cache_root.piar_lock);
+	spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags);
 	for (n = rb_first(&pci_io_addr_cache_root.rb_root); n; n = rb_next(n)) {
 		piar = rb_entry(n, struct pci_io_addr_range, rb_node);
 
@@ -273,7 +274,7 @@ static int eeh_addr_cache_show(struct seq_file *s, void *v)
 		       (piar->flags & IORESOURCE_IO) ? "i/o" : "mem",
 		       &piar->addr_lo, &piar->addr_hi, pci_name(piar->pcidev));
 	}
-	spin_unlock(&pci_io_addr_cache_root.piar_lock);
+	spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags);
 
 	return 0;
 }

arch/powerpc/kernel/head_40x.S

@@ -284,11 +284,7 @@ _ENTRY(saved_ksp_limit)
 
 	rlwimi	r11, r10, 22, 20, 29	/* Compute PTE address */
 	lwz	r11, 0(r11)		/* Get Linux PTE */
-#ifdef CONFIG_SWAP
 	li	r9, _PAGE_PRESENT | _PAGE_ACCESSED
-#else
-	li	r9, _PAGE_PRESENT
-#endif
 	andc.	r9, r9, r11		/* Check permission */
 	bne	5f
 
@@ -369,11 +365,7 @@ _ENTRY(saved_ksp_limit)
 
 	rlwimi	r11, r10, 22, 20, 29	/* Compute PTE address */
 	lwz	r11, 0(r11)		/* Get Linux PTE */
-#ifdef CONFIG_SWAP
 	li	r9, _PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
-#else
-	li	r9, _PAGE_PRESENT | _PAGE_EXEC
-#endif
 	andc.	r9, r9, r11		/* Check permission */
 	bne	5f
 

arch/powerpc/kernel/head_8xx.S

@@ -202,9 +202,7 @@ SystemCall:
 
 InstructionTLBMiss:
 	mtspr	SPRN_SPRG_SCRATCH0, r10
-#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP) || defined(CONFIG_HUGETLBFS)
 	mtspr	SPRN_SPRG_SCRATCH1, r11
-#endif
 
 	/* If we are faulting a kernel address, we have to use the
 	 * kernel page tables.
@@ -224,25 +222,13 @@ InstructionTLBMiss:
 3:
 	mtcr	r11
 #endif
-#if defined(CONFIG_HUGETLBFS) || !defined(CONFIG_PIN_TLB_TEXT)
 	lwz	r11, (swapper_pg_dir-PAGE_OFFSET)@l(r10)	/* Get level 1 entry */
 	mtspr	SPRN_MD_TWC, r11
-#else
-	lwz	r10, (swapper_pg_dir-PAGE_OFFSET)@l(r10)	/* Get level 1 entry */
-	mtspr	SPRN_MI_TWC, r10	/* Set segment attributes */
-	mtspr	SPRN_MD_TWC, r10
-#endif
 	mfspr	r10, SPRN_MD_TWC
 	lwz	r10, 0(r10)	/* Get the pte */
-#if defined(CONFIG_HUGETLBFS) || !defined(CONFIG_PIN_TLB_TEXT)
+	rlwimi	r11, r10, 0, _PAGE_GUARDED | _PAGE_ACCESSED
 	rlwimi	r11, r10, 32 - 9, _PMD_PAGE_512K
 	mtspr	SPRN_MI_TWC, r11
-#endif
-#ifdef CONFIG_SWAP
-	rlwinm	r11, r10, 32-5, _PAGE_PRESENT
-	and	r11, r11, r10
-	rlwimi	r10, r11, 0, _PAGE_PRESENT
-#endif
 	/* The Linux PTE won't go exactly into the MMU TLB.
 	 * Software indicator bits 20 and 23 must be clear.
 	 * Software indicator bits 22, 24, 25, 26, and 27 must be
@@ -256,9 +242,7 @@ InstructionTLBMiss:
 
 	/* Restore registers */
 0:	mfspr	r10, SPRN_SPRG_SCRATCH0
-#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP) || defined(CONFIG_HUGETLBFS)
 	mfspr	r11, SPRN_SPRG_SCRATCH1
-#endif
 	rfi
 	patch_site	0b, patch__itlbmiss_exit_1
 
@@ -268,9 +252,7 @@ InstructionTLBMiss:
 	addi	r10, r10, 1
 	stw	r10, (itlb_miss_counter - PAGE_OFFSET)@l(0)
 	mfspr	r10, SPRN_SPRG_SCRATCH0
-#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_SWAP)
 	mfspr	r11, SPRN_SPRG_SCRATCH1
-#endif
 	rfi
 #endif
 
@@ -297,30 +279,16 @@ DataStoreTLBMiss:
 	mfspr	r10, SPRN_MD_TWC
 	lwz	r10, 0(r10)	/* Get the pte */
 
-	/* Insert the Guarded flag into the TWC from the Linux PTE.
+	/* Insert Guarded and Accessed flags into the TWC from the Linux PTE.
 	 * It is bit 27 of both the Linux PTE and the TWC (at least
 	 * I got that right :-).  It will be better when we can put
 	 * this into the Linux pgd/pmd and load it in the operation
 	 * above.
 	 */
-	rlwimi	r11, r10, 0, _PAGE_GUARDED
+	rlwimi	r11, r10, 0, _PAGE_GUARDED | _PAGE_ACCESSED
 	rlwimi	r11, r10, 32 - 9, _PMD_PAGE_512K
 	mtspr	SPRN_MD_TWC, r11
 
-	/* Both _PAGE_ACCESSED and _PAGE_PRESENT has to be set.
-	 * We also need to know if the insn is a load/store, so:
-	 * Clear _PAGE_PRESENT and load that which will
-	 * trap into DTLB Error with store bit set accordinly.
-	 */
-	/* PRESENT=0x1, ACCESSED=0x20
-	 * r11 = ((r10 & PRESENT) & ((r10 & ACCESSED) >> 5));
-	 * r10 = (r10 & ~PRESENT) | r11;
-	 */
-#ifdef CONFIG_SWAP
-	rlwinm	r11, r10, 32-5, _PAGE_PRESENT
-	and	r11, r11, r10
-	rlwimi	r10, r11, 0, _PAGE_PRESENT
-#endif
 	/* The Linux PTE won't go exactly into the MMU TLB.
 	 * Software indicator bits 24, 25, 26, and 27 must be
 	 * set.  All other Linux PTE bits control the behavior
@@ -711,7 +679,7 @@ initial_mmu:
 	li	r9, 4				/* up to 4 pages of 8M */
 	mtctr	r9
 	lis	r9, KERNELBASE@h		/* Create vaddr for TLB */
-	li	r10, MI_PS8MEG | MI_SVALID	/* Set 8M byte page */
+	li	r10, MI_PS8MEG | _PMD_ACCESSED | MI_SVALID
 	li	r11, MI_BOOTINIT		/* Create RPN for address 0 */
 1:
 	mtspr	SPRN_MI_CTR, r8	/* Set instruction MMU control */
@@ -775,7 +743,7 @@ _GLOBAL(mmu_pin_tlb)
 #ifdef CONFIG_PIN_TLB_TEXT
 	LOAD_REG_IMMEDIATE(r5, 28 << 8)
 	LOAD_REG_IMMEDIATE(r6, PAGE_OFFSET)
-	LOAD_REG_IMMEDIATE(r7, MI_SVALID | MI_PS8MEG)
+	LOAD_REG_IMMEDIATE(r7, MI_SVALID | MI_PS8MEG | _PMD_ACCESSED)
 	LOAD_REG_IMMEDIATE(r8, 0xf0 | _PAGE_RO | _PAGE_SPS | _PAGE_SH | _PAGE_PRESENT)
 	LOAD_REG_ADDR(r9, _sinittext)
 	li	r0, 4
@@ -797,7 +765,7 @@ _GLOBAL(mmu_pin_tlb)
 	LOAD_REG_IMMEDIATE(r5, 28 << 8 | MD_TWAM)
 #ifdef CONFIG_PIN_TLB_DATA
 	LOAD_REG_IMMEDIATE(r6, PAGE_OFFSET)
-	LOAD_REG_IMMEDIATE(r7, MI_SVALID | MI_PS8MEG)
+	LOAD_REG_IMMEDIATE(r7, MI_SVALID | MI_PS8MEG | _PMD_ACCESSED)
 #ifdef CONFIG_PIN_TLB_IMMR
 	li	r0, 3
 #else
@@ -834,7 +802,7 @@ _GLOBAL(mmu_pin_tlb)
 #endif
 #ifdef CONFIG_PIN_TLB_IMMR
 	LOAD_REG_IMMEDIATE(r0, VIRT_IMMR_BASE | MD_EVALID)
-	LOAD_REG_IMMEDIATE(r7, MD_SVALID | MD_PS512K | MD_GUARDED)
+	LOAD_REG_IMMEDIATE(r7, MD_SVALID | MD_PS512K | MD_GUARDED | _PMD_ACCESSED)
 	mfspr   r8, SPRN_IMMR
 	rlwinm	r8, r8, 0, 0xfff80000
 	ori	r8, r8, 0xf0 | _PAGE_DIRTY | _PAGE_SPS | _PAGE_SH | \

arch/powerpc/kernel/head_book3s_32.S

@@ -457,11 +457,7 @@ InstructionTLBMiss:
 	cmplw	0,r1,r3
 #endif
 	mfspr	r2, SPRN_SPRG_PGDIR
-#ifdef CONFIG_SWAP
 	li	r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
-#else
-	li	r1,_PAGE_PRESENT | _PAGE_EXEC
-#endif
 #if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC)
 	bgt-	112f
 	lis	r2, (swapper_pg_dir - PAGE_OFFSET)@ha	/* if kernel address, use */
@@ -523,11 +519,7 @@ DataLoadTLBMiss:
 	lis	r1, TASK_SIZE@h		/* check if kernel address */
 	cmplw	0,r1,r3
 	mfspr	r2, SPRN_SPRG_PGDIR
-#ifdef CONFIG_SWAP
 	li	r1, _PAGE_PRESENT | _PAGE_ACCESSED
-#else
-	li	r1, _PAGE_PRESENT
-#endif
 	bgt-	112f
 	lis	r2, (swapper_pg_dir - PAGE_OFFSET)@ha	/* if kernel address, use */
 	addi	r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l	/* kernel page table */
@@ -603,11 +595,7 @@ DataStoreTLBMiss:
 	lis	r1, TASK_SIZE@h		/* check if kernel address */
 	cmplw	0,r1,r3
 	mfspr	r2, SPRN_SPRG_PGDIR
-#ifdef CONFIG_SWAP
 	li	r1, _PAGE_RW | _PAGE_DIRTY | _PAGE_PRESENT | _PAGE_ACCESSED
-#else
-	li	r1, _PAGE_RW | _PAGE_DIRTY | _PAGE_PRESENT
-#endif
 	bgt-	112f
 	lis	r2, (swapper_pg_dir - PAGE_OFFSET)@ha	/* if kernel address, use */
 	addi	r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l	/* kernel page table */

arch/powerpc/kernel/smp.c

@@ -1393,13 +1393,14 @@ static void add_cpu_to_masks(int cpu)
 /* Activate a secondary processor. */
 void start_secondary(void *unused)
 {
-	unsigned int cpu = smp_processor_id();
+	unsigned int cpu = raw_smp_processor_id();
 
 	mmgrab(&init_mm);
 	current->active_mm = &init_mm;
 
 	smp_store_cpu_info(cpu);
 	set_dec(tb_ticks_per_jiffy);
+	rcu_cpu_starting(cpu);
 	preempt_disable();
 	cpu_callin_map[cpu] = 1;