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

2 files changed, 10 insertions, 1 deletions

diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c
index 9a5963e07a82..b8ad14bb1170 100644
--- a/arch/powerpc/mm/book3s64/hash_utils.c
+++ b/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);
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 9259337d7374..9191a66b3bc5 100644
--- a/arch/powerpc/mm/mem.c
+++ b/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