Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

Pull ARM fixes from Russell King:

 - quieten the spectre-bhb prints

 - mark flattened device tree sections as shareable

 - remove some obsolete CPU domain code and help text

 - fix thumb unaligned access abort emulation

 - fix amba_device_add() refcount underflow

 - fix literal placement

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 9208/1: entry: add .ltorg directive to keep literals in range
  ARM: 9207/1: amba: fix refcount underflow if amba_device_add() fails
  ARM: 9214/1: alignment: advance IT state after emulating Thumb instruction
  ARM: 9213/1: Print message about disabled Spectre workarounds only once
  ARM: 9212/1: domain: Modify Kconfig help text
  ARM: 9211/1: domain: drop modify_domain()
  ARM: 9210/1: Mark the FDT_FIXED sections as shareable
  ARM: 9209/1: Spectre-BHB: avoid pr_info() every time a CPU comes out of idle

Author: torvalds

arch/arm/include/asm/domain.h

@@ -112,19 +112,6 @@ static __always_inline void set_domain(unsigned int val)
 }
 #endif
 
-#ifdef CONFIG_CPU_USE_DOMAINS
-#define modify_domain(dom,type)					\
-	do {							\
-		unsigned int domain = get_domain();		\
-		domain &= ~domain_mask(dom);			\
-		domain = domain | domain_val(dom, type);	\
-		set_domain(domain);				\
-	} while (0)
-
-#else
-static inline void modify_domain(unsigned dom, unsigned type)	{ }
-#endif
-
 /*
  * Generate the T (user) versions of the LDR/STR and related
  * instructions (inline assembly)

arch/arm/include/asm/mach/map.h

@@ -27,6 +27,7 @@ enum {
 	MT_HIGH_VECTORS,
 	MT_MEMORY_RWX,
 	MT_MEMORY_RW,
+	MT_MEMORY_RO,
 	MT_ROM,
 	MT_MEMORY_RWX_NONCACHED,
 	MT_MEMORY_RW_DTCM,

arch/arm/include/asm/ptrace.h

@@ -163,5 +163,31 @@ static inline unsigned long user_stack_pointer(struct pt_regs *regs)
 		((current_stack_pointer | (THREAD_SIZE - 1)) - 7) - 1;	\
 })
 
+
+/*
+ * Update ITSTATE after normal execution of an IT block instruction.
+ *
+ * The 8 IT state bits are split into two parts in CPSR:
+ *	ITSTATE<1:0> are in CPSR<26:25>
+ *	ITSTATE<7:2> are in CPSR<15:10>
+ */
+static inline unsigned long it_advance(unsigned long cpsr)
+{
+	if ((cpsr & 0x06000400) == 0) {
+		/* ITSTATE<2:0> == 0 means end of IT block, so clear IT state */
+		cpsr &= ~PSR_IT_MASK;
+	} else {
+		/* We need to shift left ITSTATE<4:0> */
+		const unsigned long mask = 0x06001c00;  /* Mask ITSTATE<4:0> */
+		unsigned long it = cpsr & mask;
+		it <<= 1;
+		it |= it >> (27 - 10);  /* Carry ITSTATE<2> to correct place */
+		it &= mask;
+		cpsr &= ~mask;
+		cpsr |= it;
+	}
+	return cpsr;
+}
+
 #endif /* __ASSEMBLY__ */
 #endif

arch/arm/kernel/entry-common.S

@@ -302,6 +302,7 @@ local_restart:
 	b	ret_fast_syscall
 #endif
 ENDPROC(vector_swi)
+	.ltorg
 
 	/*
 	 * This is the really slow path.  We're going to be doing

arch/arm/mm/Kconfig

@@ -631,7 +631,11 @@ config CPU_USE_DOMAINS
 	bool
 	help
 	  This option enables or disables the use of domain switching
-	  via the set_fs() function.
+	  using the DACR (domain access control register) to protect memory
+	  domains from each other. In Linux we use three domains: kernel, user
+	  and IO. The domains are used to protect userspace from kernelspace
+	  and to handle IO-space as a special type of memory by assigning
+	  manager or client roles to running code (such as a process).
 
 config CPU_V7M_NUM_IRQ
 	int "Number of external interrupts connected to the NVIC"

arch/arm/mm/alignment.c

@@ -935,6 +935,9 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 	if (type == TYPE_LDST)
 		do_alignment_finish_ldst(addr, instr, regs, offset);
 
+	if (thumb_mode(regs))
+		regs->ARM_cpsr = it_advance(regs->ARM_cpsr);
+
 	return 0;
 
  bad_or_fault:

arch/arm/mm/mmu.c

@@ -296,6 +296,13 @@ static struct mem_type mem_types[] __ro_after_init = {
 		.prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
 		.domain    = DOMAIN_KERNEL,
 	},
+	[MT_MEMORY_RO] = {
+		.prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+			     L_PTE_XN | L_PTE_RDONLY,
+		.prot_l1   = PMD_TYPE_TABLE,
+		.prot_sect = PMD_TYPE_SECT,
+		.domain    = DOMAIN_KERNEL,
+	},
 	[MT_ROM] = {
 		.prot_sect = PMD_TYPE_SECT,
 		.domain    = DOMAIN_KERNEL,
@@ -489,6 +496,7 @@ static void __init build_mem_type_table(void)
 
 			/* Also setup NX memory mapping */
 			mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_XN;
+			mem_types[MT_MEMORY_RO].prot_sect |= PMD_SECT_XN;
 		}
 		if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
 			/*
@@ -568,6 +576,7 @@ static void __init build_mem_type_table(void)
 		mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
 		mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
 		mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
+		mem_types[MT_MEMORY_RO].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
 #endif
 
 		/*
@@ -587,6 +596,8 @@ static void __init build_mem_type_table(void)
 			mem_types[MT_MEMORY_RWX].prot_pte |= L_PTE_SHARED;
 			mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_S;
 			mem_types[MT_MEMORY_RW].prot_pte |= L_PTE_SHARED;
+			mem_types[MT_MEMORY_RO].prot_sect |= PMD_SECT_S;
+			mem_types[MT_MEMORY_RO].prot_pte |= L_PTE_SHARED;
 			mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
 			mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_S;
 			mem_types[MT_MEMORY_RWX_NONCACHED].prot_pte |= L_PTE_SHARED;
@@ -647,6 +658,8 @@ static void __init build_mem_type_table(void)
 	mem_types[MT_MEMORY_RWX].prot_pte |= kern_pgprot;
 	mem_types[MT_MEMORY_RW].prot_sect |= ecc_mask | cp->pmd;
 	mem_types[MT_MEMORY_RW].prot_pte |= kern_pgprot;
+	mem_types[MT_MEMORY_RO].prot_sect |= ecc_mask | cp->pmd;
+	mem_types[MT_MEMORY_RO].prot_pte |= kern_pgprot;
 	mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot;
 	mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= ecc_mask;
 	mem_types[MT_ROM].prot_sect |= cp->pmd;
@@ -1360,7 +1373,7 @@ static void __init devicemaps_init(const struct machine_desc *mdesc)
 		map.pfn = __phys_to_pfn(__atags_pointer & SECTION_MASK);
 		map.virtual = FDT_FIXED_BASE;
 		map.length = FDT_FIXED_SIZE;
-		map.type = MT_ROM;
+		map.type = MT_MEMORY_RO;
 		create_mapping(&map);
 	}
 

arch/arm/mm/proc-v7-bugs.c

@@ -108,8 +108,7 @@ static unsigned int spectre_v2_install_workaround(unsigned int method)
 #else
 static unsigned int spectre_v2_install_workaround(unsigned int method)
 {
-	pr_info("CPU%u: Spectre V2: workarounds disabled by configuration\n",
-		smp_processor_id());
+	pr_info_once("Spectre V2: workarounds disabled by configuration\n");
 
 	return SPECTRE_VULNERABLE;
 }
@@ -209,10 +208,10 @@ static int spectre_bhb_install_workaround(int method)
 			return SPECTRE_VULNERABLE;
 
 		spectre_bhb_method = method;
-	}
 
-	pr_info("CPU%u: Spectre BHB: using %s workaround\n",
-		smp_processor_id(), spectre_bhb_method_name(method));
+		pr_info("CPU%u: Spectre BHB: enabling %s workaround for all CPUs\n",
+			smp_processor_id(), spectre_bhb_method_name(method));
+	}
 
 	return SPECTRE_MITIGATED;
 }

arch/arm/probes/decode.h

@@ -14,6 +14,7 @@
 #include <linux/types.h>
 #include <linux/stddef.h>
 #include <asm/probes.h>
+#include <asm/ptrace.h>
 #include <asm/kprobes.h>
 
 void __init arm_probes_decode_init(void);
@@ -35,31 +36,6 @@ void __init find_str_pc_offset(void);
 #endif
 
 
-/*
- * Update ITSTATE after normal execution of an IT block instruction.
- *
- * The 8 IT state bits are split into two parts in CPSR:
- *	ITSTATE<1:0> are in CPSR<26:25>
- *	ITSTATE<7:2> are in CPSR<15:10>
- */
-static inline unsigned long it_advance(unsigned long cpsr)
-	{
-	if ((cpsr & 0x06000400) == 0) {
-		/* ITSTATE<2:0> == 0 means end of IT block, so clear IT state */
-		cpsr &= ~PSR_IT_MASK;
-	} else {
-		/* We need to shift left ITSTATE<4:0> */
-		const unsigned long mask = 0x06001c00;  /* Mask ITSTATE<4:0> */
-		unsigned long it = cpsr & mask;
-		it <<= 1;
-		it |= it >> (27 - 10);  /* Carry ITSTATE<2> to correct place */
-		it &= mask;
-		cpsr &= ~mask;
-		cpsr |= it;
-	}
-	return cpsr;
-}
-
 static inline void __kprobes bx_write_pc(long pcv, struct pt_regs *regs)
 {
 	long cpsr = regs->ARM_cpsr;

drivers/amba/bus.c

@@ -493,13 +493,8 @@ static int amba_device_try_add(struct amba_device *dev, struct resource *parent)
 		goto skip_probe;
 
 	ret = amba_read_periphid(dev);
-	if (ret) {
-		if (ret != -EPROBE_DEFER) {
-			amba_device_put(dev);
-			goto err_out;
-		}
+	if (ret)
 		goto err_release;
-	}
 
 skip_probe:
 	ret = device_add(&dev->dev);
@@ -546,6 +541,7 @@ static int amba_deferred_retry(void)
 			continue;
 
 		list_del_init(&ddev->node);
+		amba_device_put(ddev->dev);
 		kfree(ddev);
 	}