Merge tag 'powerpc-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "An assortment of non-regression fixes that have accumulated since the
  start of the merge window.

   - A fix for a user triggerable oops on machines where transactional
     memory is disabled, eg. Power9 bare metal, Power8 with TM disabled
     on the command line, or all Power7 or earlier machines.

   - Three fixes for handling of PMU and power saving registers when
     running nested KVM on Power9.

   - Two fixes for bugs found while stress testing the XIVE interrupt
     controller code, also on Power9.

   - A fix to allow guests to boot under Qemu/KVM on Power9 using the
     the Hash MMU with >= 1TB of memory.

   - Two fixes for bugs in the recent DMA cleanup, one of which could
     lead to checkstops.

   - And finally three fixes for the PAPR SCM nvdimm driver.

  Thanks to: Alexey Kardashevskiy, Andrea Arcangeli, Cédric Le Goater,
  Christoph Hellwig, David Gibson, Gautham R. Shenoy, Michael Neuling,
  Oliver O'Halloran, Satheesh Rajendran, Shawn Anastasio, Suraj Jitindar
  Singh, Vaibhav Jain"

* tag 'powerpc-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/papr_scm: Force a scm-unbind if initial scm-bind fails
  powerpc/papr_scm: Update drc_pmem_unbind() to use H_SCM_UNBIND_ALL
  powerpc/pseries: Update SCM hcall op-codes in hvcall.h
  powerpc/tm: Fix oops on sigreturn on systems without TM
  powerpc/dma: Fix invalid DMA mmap behavior
  KVM: PPC: Book3S HV: XIVE: fix rollback when kvmppc_xive_create fails
  powerpc/xive: Fix loop exit-condition in xive_find_target_in_mask()
  powerpc: fix off by one in max_zone_pfn initialization for ZONE_DMA
  KVM: PPC: Book3S HV: Save and restore guest visible PSSCR bits on pseries
  powerpc/pmu: Set pmcregs_in_use in paca when running as LPAR
  KVM: PPC: Book3S HV: Always save guest pmu for guest capable of nesting
  powerpc/mm: Limit rma_size to 1TB when running without HV mode

arch/powerpc/Kconfig

@@ -121,6 +121,7 @@ config PPC
 	select ARCH_32BIT_OFF_T if PPC32
 	select ARCH_HAS_DEBUG_VIRTUAL
 	select ARCH_HAS_DEVMEM_IS_ALLOWED
+	select ARCH_HAS_DMA_MMAP_PGPROT
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL

arch/powerpc/include/asm/hvcall.h

@@ -302,9 +302,14 @@
 #define H_SCM_UNBIND_MEM        0x3F0
 #define H_SCM_QUERY_BLOCK_MEM_BINDING 0x3F4
 #define H_SCM_QUERY_LOGICAL_MEM_BINDING 0x3F8
-#define H_SCM_MEM_QUERY	        0x3FC
-#define H_SCM_BLOCK_CLEAR       0x400
-#define MAX_HCALL_OPCODE	H_SCM_BLOCK_CLEAR
+#define H_SCM_UNBIND_ALL        0x3FC
+#define H_SCM_HEALTH            0x400
+#define H_SCM_PERFORMANCE_STATS 0x418
+#define MAX_HCALL_OPCODE	H_SCM_PERFORMANCE_STATS
+
+/* Scope args for H_SCM_UNBIND_ALL */
+#define H_UNBIND_SCOPE_ALL (0x1)
+#define H_UNBIND_SCOPE_DRC (0x2)
 
 /* H_VIOCTL functions */
 #define H_GET_VIOA_DUMP_SIZE	0x01

arch/powerpc/include/asm/pmc.h

@@ -27,11 +27,10 @@ static inline void ppc_set_pmu_inuse(int inuse)
 #ifdef CONFIG_PPC_PSERIES
 		get_lppaca()->pmcregs_in_use = inuse;
 #endif
-	} else {
+	}
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-		get_paca()->pmcregs_in_use = inuse;
+	get_paca()->pmcregs_in_use = inuse;
 #endif
-	}
 #endif
 }
 

arch/powerpc/kernel/Makefile

@@ -49,7 +49,8 @@ obj-y				:= cputable.o ptrace.o syscalls.o \
 				   signal.o sysfs.o cacheinfo.o time.o \
 				   prom.o traps.o setup-common.o \
 				   udbg.o misc.o io.o misc_$(BITS).o \
-				   of_platform.o prom_parse.o
+				   of_platform.o prom_parse.o \
+				   dma-common.o
 obj-$(CONFIG_PPC64)		+= setup_64.o sys_ppc32.o \
 				   signal_64.o ptrace32.o \
 				   paca.o nvram_64.o firmware.o

arch/powerpc/kernel/dma-common.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Contains common dma routines for all powerpc platforms.
+ *
+ * Copyright (C) 2019 Shawn Anastasio.
+ */
+
+#include <linux/mm.h>
+#include <linux/dma-noncoherent.h>
+
+pgprot_t arch_dma_mmap_pgprot(struct device *dev, pgprot_t prot,
+		unsigned long attrs)
+{
+	if (!dev_is_dma_coherent(dev))
+		return pgprot_noncached(prot);
+	return prot;
+}

arch/powerpc/kernel/signal_32.c

@@ -1198,6 +1198,9 @@ SYSCALL_DEFINE0(rt_sigreturn)
 			goto bad;
 
 		if (MSR_TM_ACTIVE(msr_hi<<32)) {
+			/* Trying to start TM on non TM system */
+			if (!cpu_has_feature(CPU_FTR_TM))
+				goto bad;
 			/* We only recheckpoint on return if we're
 			 * transaction.
 			 */

arch/powerpc/kernel/signal_64.c

@@ -771,6 +771,11 @@ SYSCALL_DEFINE0(rt_sigreturn)
 	if (MSR_TM_ACTIVE(msr)) {
 		/* We recheckpoint on return. */
 		struct ucontext __user *uc_transact;
+
+		/* Trying to start TM on non TM system */
+		if (!cpu_has_feature(CPU_FTR_TM))
+			goto badframe;
+
 		if (__get_user(uc_transact, &uc->uc_link))
 			goto badframe;
 		if (restore_tm_sigcontexts(current, &uc->uc_mcontext,

arch/powerpc/kvm/book3s_hv.c

@@ -3569,9 +3569,18 @@ int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 	mtspr(SPRN_DEC, vcpu->arch.dec_expires - mftb());
 
 	if (kvmhv_on_pseries()) {
+		/*
+		 * We need to save and restore the guest visible part of the
+		 * psscr (i.e. using SPRN_PSSCR_PR) since the hypervisor
+		 * doesn't do this for us. Note only required if pseries since
+		 * this is done in kvmhv_load_hv_regs_and_go() below otherwise.
+		 */
+		unsigned long host_psscr;
 		/* call our hypervisor to load up HV regs and go */
 		struct hv_guest_state hvregs;
 
+		host_psscr = mfspr(SPRN_PSSCR_PR);
+		mtspr(SPRN_PSSCR_PR, vcpu->arch.psscr);
 		kvmhv_save_hv_regs(vcpu, &hvregs);
 		hvregs.lpcr = lpcr;
 		vcpu->arch.regs.msr = vcpu->arch.shregs.msr;
@@ -3590,6 +3599,8 @@ int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 		vcpu->arch.shregs.msr = vcpu->arch.regs.msr;
 		vcpu->arch.shregs.dar = mfspr(SPRN_DAR);
 		vcpu->arch.shregs.dsisr = mfspr(SPRN_DSISR);
+		vcpu->arch.psscr = mfspr(SPRN_PSSCR_PR);
+		mtspr(SPRN_PSSCR_PR, host_psscr);
 
 		/* H_CEDE has to be handled now, not later */
 		if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
@@ -3654,6 +3665,8 @@ int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 		vcpu->arch.vpa.dirty = 1;
 		save_pmu = lp->pmcregs_in_use;
 	}
+	/* Must save pmu if this guest is capable of running nested guests */
+	save_pmu |= nesting_enabled(vcpu->kvm);
 
 	kvmhv_save_guest_pmu(vcpu, save_pmu);
 

arch/powerpc/kvm/book3s_xive.c

@@ -1986,10 +1986,8 @@ static int kvmppc_xive_create(struct kvm_device *dev, u32 type)
 
 	xive->single_escalation = xive_native_has_single_escalation();
 
-	if (ret) {
-		kfree(xive);
+	if (ret)
 		return ret;
-	}
 
 	return 0;
 }

arch/powerpc/kvm/book3s_xive_native.c

@@ -1090,9 +1090,9 @@ static int kvmppc_xive_native_create(struct kvm_device *dev, u32 type)
 	xive->ops = &kvmppc_xive_native_ops;
 
 	if (ret)
-		kfree(xive);
+		return ret;
 
-	return ret;
+	return 0;
 }
 
 /*

arch/powerpc/mm/book3s64/hash_utils.c

@@ -1899,11 +1899,20 @@ void hash__setup_initial_memory_limit(phys_addr_t first_memblock_base,
 	 *
 	 * For guests on platforms before POWER9, we clamp the it limit to 1G
 	 * to avoid some funky things such as RTAS bugs etc...
+	 *
+	 * On POWER9 we limit to 1TB in case the host erroneously told us that
+	 * the RMA was >1TB. Effective address bits 0:23 are treated as zero
+	 * (meaning the access is aliased to zero i.e. addr = addr % 1TB)
+	 * for virtual real mode addressing and so it doesn't make sense to
+	 * have an area larger than 1TB as it can't be addressed.
 	 */
 	if (!early_cpu_has_feature(CPU_FTR_HVMODE)) {
 		ppc64_rma_size = first_memblock_size;
 		if (!early_cpu_has_feature(CPU_FTR_ARCH_300))
 			ppc64_rma_size = min_t(u64, ppc64_rma_size, 0x40000000);
+		else
+			ppc64_rma_size = min_t(u64, ppc64_rma_size,
+					       1UL << SID_SHIFT_1T);
 
 		/* Finally limit subsequent allocations */
 		memblock_set_current_limit(ppc64_rma_size);

arch/powerpc/mm/mem.c

@@ -239,7 +239,7 @@ void __init paging_init(void)
 
 #ifdef CONFIG_ZONE_DMA
 	max_zone_pfns[ZONE_DMA]	= min(max_low_pfn,
-			((1UL << ARCH_ZONE_DMA_BITS) - 1) >> PAGE_SHIFT);
+				      1UL << (ARCH_ZONE_DMA_BITS - PAGE_SHIFT));
 #endif
 	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 #ifdef CONFIG_HIGHMEM

arch/powerpc/platforms/pseries/papr_scm.c

@@ -11,6 +11,7 @@
 #include <linux/sched.h>
 #include <linux/libnvdimm.h>
 #include <linux/platform_device.h>
+#include <linux/delay.h>
 
 #include <asm/plpar_wrappers.h>
 
@@ -43,8 +44,9 @@ struct papr_scm_priv {
 static int drc_pmem_bind(struct papr_scm_priv *p)
 {
 	unsigned long ret[PLPAR_HCALL_BUFSIZE];
-	uint64_t rc, token;
 	uint64_t saved = 0;
+	uint64_t token;
+	int64_t rc;
 
 	/*
 	 * When the hypervisor cannot map all the requested memory in a single
@@ -64,6 +66,10 @@ static int drc_pmem_bind(struct papr_scm_priv *p)
 	} while (rc == H_BUSY);
 
 	if (rc) {
+		/* H_OVERLAP needs a separate error path */
+		if (rc == H_OVERLAP)
+			return -EBUSY;
+
 		dev_err(&p->pdev->dev, "bind err: %lld\n", rc);
 		return -ENXIO;
 	}
@@ -78,22 +84,36 @@ static int drc_pmem_bind(struct papr_scm_priv *p)
 static int drc_pmem_unbind(struct papr_scm_priv *p)
 {
 	unsigned long ret[PLPAR_HCALL_BUFSIZE];
-	uint64_t rc, token;
+	uint64_t token = 0;
+	int64_t rc;
 
-	token = 0;
+	dev_dbg(&p->pdev->dev, "unbind drc %x\n", p->drc_index);
 
-	/* NB: unbind has the same retry requirements mentioned above */
+	/* NB: unbind has the same retry requirements as drc_pmem_bind() */
 	do {
-		rc = plpar_hcall(H_SCM_UNBIND_MEM, ret, p->drc_index,
-				p->bound_addr, p->blocks, token);
+
+		/* Unbind of all SCM resources associated with drcIndex */
+		rc = plpar_hcall(H_SCM_UNBIND_ALL, ret, H_UNBIND_SCOPE_DRC,
+				 p->drc_index, token);
 		token = ret[0];
-		cond_resched();
+
+		/* Check if we are stalled for some time */
+		if (H_IS_LONG_BUSY(rc)) {
+			msleep(get_longbusy_msecs(rc));
+			rc = H_BUSY;
+		} else if (rc == H_BUSY) {
+			cond_resched();
+		}
+
 	} while (rc == H_BUSY);
 
 	if (rc)
 		dev_err(&p->pdev->dev, "unbind error: %lld\n", rc);
+	else
+		dev_dbg(&p->pdev->dev, "unbind drc %x complete\n",
+			p->drc_index);
 
-	return !!rc;
+	return rc == H_SUCCESS ? 0 : -ENXIO;
 }
 
 static int papr_scm_meta_get(struct papr_scm_priv *p,
@@ -389,6 +409,14 @@ static int papr_scm_probe(struct platform_device *pdev)
 
 	/* request the hypervisor to bind this region to somewhere in memory */
 	rc = drc_pmem_bind(p);
+
+	/* If phyp says drc memory still bound then force unbound and retry */
+	if (rc == -EBUSY) {
+		dev_warn(&pdev->dev, "Retrying bind after unbinding\n");
+		drc_pmem_unbind(p);
+		rc = drc_pmem_bind(p);
+	}
+
 	if (rc)
 		goto err;
 

arch/powerpc/sysdev/xive/common.c

@@ -479,7 +479,7 @@ static int xive_find_target_in_mask(const struct cpumask *mask,
 	 * Now go through the entire mask until we find a valid
 	 * target.
 	 */
-	for (;;) {
+	do {
 		/*
 		 * We re-check online as the fallback case passes us
 		 * an untested affinity mask
@@ -487,12 +487,11 @@ static int xive_find_target_in_mask(const struct cpumask *mask,
 		if (cpu_online(cpu) && xive_try_pick_target(cpu))
 			return cpu;
 		cpu = cpumask_next(cpu, mask);
-		if (cpu == first)
-			break;
 		/* Wrap around */
 		if (cpu >= nr_cpu_ids)
 			cpu = cpumask_first(mask);
-	}
+	} while (cpu != first);
+
 	return -1;
 }