Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "An unfortunately large collection of arm64 fixes for -rc5.

  Some of this is absolutely trivial, but the alternatives, vDSO and CPU
  errata workaround fixes are significant. At least people are finding
  and fixing these things, I suppose.

   - Fix workaround for CPU erratum #1418040 to disable the compat vDSO

   - Fix Oops when single-stepping with KGDB

   - Fix memory attributes for hypervisor device mappings at EL2

   - Fix memory leak in PSCI and remove useless variable assignment

   - Fix up some comments and asm labels in our entry code

   - Fix broken register table formatting in our generated html docs

   - Fix missing NULL sentinel in CPU errata workaround list

   - Fix patching of branches in alternative instruction sections"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64/alternatives: don't patch up internal branches
  arm64: Add missing sentinel to erratum_1463225
  arm64: Documentation: Fix broken table in generated HTML
  arm64: kgdb: Fix single-step exception handling oops
  arm64: entry: Tidy up block comments and label numbers
  arm64: Rework ARM_ERRATUM_1414080 handling
  arm64: arch_timer: Disable the compat vdso for cores affected by ARM64_WORKAROUND_1418040
  arm64: arch_timer: Allow an workaround descriptor to disable compat vdso
  arm64: Introduce a way to disable the 32bit vdso
  arm64: entry: Fix the typo in the comment of el1_dbg()
  drivers/firmware/psci: Assign @err directly in hotplug_tests()
  drivers/firmware/psci: Fix memory leakage in alloc_init_cpu_groups()
  KVM: arm64: Fix definition of PAGE_HYP_DEVICE

5 files changed, 36 insertions, 37 deletions

diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c
index d1757ef1b1e7..73039949b5ce 100644
--- a/arch/arm64/kernel/alternative.c
+++ b/arch/arm64/kernel/alternative.c
@@ -43,20 +43,8 @@ bool alternative_is_applied(u16 cpufeature)
  */
 static bool branch_insn_requires_update(struct alt_instr *alt, unsigned long pc)
 {
-	unsigned long replptr;
-
-	if (kernel_text_address(pc))
-		return true;
-
-	replptr = (unsigned long)ALT_REPL_PTR(alt);
-	if (pc >= replptr && pc <= (replptr + alt->alt_len))
-		return false;
-
-	/*
-	 * Branching into *another* alternate sequence is doomed, and
-	 * we're not even trying to fix it up.
-	 */
-	BUG();
+	unsigned long replptr = (unsigned long)ALT_REPL_PTR(alt);
+	return !(pc >= replptr && pc <= (replptr + alt->alt_len));
 }
 
 #define align_down(x, a)	((unsigned long)(x) & ~(((unsigned long)(a)) - 1))
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 8e302dc093d0..79728bfb5351 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -782,6 +782,7 @@ static const struct midr_range erratum_1463225[] = {
 	MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 3, 1),
 	/* Kryo4xx Gold (rcpe to rfpf) => (r0p0 to r3p1) */
 	MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xf),
+	{},
 };
 #endif
 
diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c
index 3dbdf9752b11..d3be9dbf5490 100644
--- a/arch/arm64/kernel/entry-common.c
+++ b/arch/arm64/kernel/entry-common.c
@@ -57,7 +57,7 @@ static void notrace el1_dbg(struct pt_regs *regs, unsigned long esr)
 	/*
 	 * The CPU masked interrupts, and we are leaving them masked during
 	 * do_debug_exception(). Update PMR as if we had called
-	 * local_mask_daif().
+	 * local_daif_mask().
 	 */
 	if (system_uses_irq_prio_masking())
 		gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 5304d193c79d..35de8ba60e3d 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -126,8 +126,10 @@ alternative_else_nop_endif
 	add	\dst, \dst, #(\sym - .entry.tramp.text)
 	.endm
 
-	// This macro corrupts x0-x3. It is the caller's duty
-	// to save/restore them if required.
+	/*
+	 * This macro corrupts x0-x3. It is the caller's duty  to save/restore
+	 * them if required.
+	 */
 	.macro	apply_ssbd, state, tmp1, tmp2
 #ifdef CONFIG_ARM64_SSBD
 alternative_cb	arm64_enable_wa2_handling
@@ -167,13 +169,28 @@ alternative_cb_end
 	stp	x28, x29, [sp, #16 * 14]
 
 	.if	\el == 0
+	.if	\regsize == 32
+	/*
+	 * If we're returning from a 32-bit task on a system affected by
+	 * 1418040 then re-enable userspace access to the virtual counter.
+	 */
+#ifdef CONFIG_ARM64_ERRATUM_1418040
+alternative_if ARM64_WORKAROUND_1418040
+	mrs	x0, cntkctl_el1
+	orr	x0, x0, #2	// ARCH_TIMER_USR_VCT_ACCESS_EN
+	msr	cntkctl_el1, x0
+alternative_else_nop_endif
+#endif
+	.endif
 	clear_gp_regs
 	mrs	x21, sp_el0
 	ldr_this_cpu	tsk, __entry_task, x20
 	msr	sp_el0, tsk
 
-	// Ensure MDSCR_EL1.SS is clear, since we can unmask debug exceptions
-	// when scheduling.
+	/*
+	 * Ensure MDSCR_EL1.SS is clear, since we can unmask debug exceptions
+	 * when scheduling.
+	 */
 	ldr	x19, [tsk, #TSK_TI_FLAGS]
 	disable_step_tsk x19, x20
 
@@ -320,6 +337,14 @@ alternative_else_nop_endif
 	tst	x22, #PSR_MODE32_BIT		// native task?
 	b.eq	3f
 
+#ifdef CONFIG_ARM64_ERRATUM_1418040
+alternative_if ARM64_WORKAROUND_1418040
+	mrs	x0, cntkctl_el1
+	bic	x0, x0, #2			// ARCH_TIMER_USR_VCT_ACCESS_EN
+	msr	cntkctl_el1, x0
+alternative_else_nop_endif
+#endif
+
 #ifdef CONFIG_ARM64_ERRATUM_845719
 alternative_if ARM64_WORKAROUND_845719
 #ifdef CONFIG_PID_IN_CONTEXTIDR
@@ -331,21 +356,6 @@ alternative_if ARM64_WORKAROUND_845719
 alternative_else_nop_endif
 #endif
 3:
-#ifdef CONFIG_ARM64_ERRATUM_1418040
-alternative_if_not ARM64_WORKAROUND_1418040
-	b	4f
-alternative_else_nop_endif
-	/*
-	 * if (x22.mode32 == cntkctl_el1.el0vcten)
-	 *     cntkctl_el1.el0vcten = ~cntkctl_el1.el0vcten
-	 */
-	mrs	x1, cntkctl_el1
-	eon	x0, x1, x22, lsr #3
-	tbz	x0, #1, 4f
-	eor	x1, x1, #2	// ARCH_TIMER_USR_VCT_ACCESS_EN
-	msr	cntkctl_el1, x1
-4:
-#endif
 	scs_save tsk, x0
 
 	/* No kernel C function calls after this as user keys are set. */
@@ -377,11 +387,11 @@ alternative_else_nop_endif
 	.if	\el == 0
 alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-	bne	5f
+	bne	4f
 	msr	far_el1, x30
 	tramp_alias	x30, tramp_exit_native
 	br	x30
-5:
+4:
 	tramp_alias	x30, tramp_exit_compat
 	br	x30
 #endif
diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c
index 43119922341f..1a157ca33262 100644
--- a/arch/arm64/kernel/kgdb.c
+++ b/arch/arm64/kernel/kgdb.c
@@ -252,7 +252,7 @@ static int kgdb_step_brk_fn(struct pt_regs *regs, unsigned int esr)
 	if (!kgdb_single_step)
 		return DBG_HOOK_ERROR;
 
-	kgdb_handle_exception(1, SIGTRAP, 0, regs);
+	kgdb_handle_exception(0, SIGTRAP, 0, regs);
 	return DBG_HOOK_HANDLED;
 }
 NOKPROBE_SYMBOL(kgdb_step_brk_fn);