Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Martin Schwidefsky:
 - A proper fix for the locking issue in the dasd driver
 - Wire up the new preadv2 nad pwritev2 system calls
 - Add the mark_rodata_ro function and set DEBUG_RODATA=y
 - A few more bug fixes.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: wire up preadv2/pwritev2 syscalls
  s390/pci: PCI function group 0 is valid for clp_query_pci_fn
  s390/crypto: provide correct file mode at device register.
  s390/mm: handle PTE-mapped tail pages in fast gup
  s390: add DEBUG_RODATA support
  s390: disable postinit-readonly for now
  s390/dasd: reorder lcu and device lock
  s390/cpum_sf: Fix cpu hotplug notifier transitions
  s390/cpum_cf: Fix missing cpu hotplug notifier transition

10 files changed, 28 insertions, 10 deletions

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index b9df8d11d7a9..aad23e3dff2c 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -59,6 +59,9 @@ config PCI_QUIRKS
 config ARCH_SUPPORTS_UPROBES
 	def_bool y
 
+config DEBUG_RODATA
+	def_bool y
+
 config S390
 	def_bool y
 	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
diff --git a/arch/s390/crypto/prng.c b/arch/s390/crypto/prng.c
index b8045b97f4fb..d750cc0dfe30 100644
--- a/arch/s390/crypto/prng.c
+++ b/arch/s390/crypto/prng.c
@@ -669,11 +669,13 @@ static const struct file_operations prng_tdes_fops = {
 static struct miscdevice prng_sha512_dev = {
 	.name	= "prandom",
 	.minor	= MISC_DYNAMIC_MINOR,
+	.mode	= 0644,
 	.fops	= &prng_sha512_fops,
 };
 static struct miscdevice prng_tdes_dev = {
 	.name	= "prandom",
 	.minor	= MISC_DYNAMIC_MINOR,
+	.mode	= 0644,
 	.fops	= &prng_tdes_fops,
 };
 
diff --git a/arch/s390/include/asm/cache.h b/arch/s390/include/asm/cache.h
index 4d7ccac5fd1d..22da3b34c655 100644
--- a/arch/s390/include/asm/cache.h
+++ b/arch/s390/include/asm/cache.h
@@ -15,4 +15,7 @@
 
 #define __read_mostly __attribute__((__section__(".data..read_mostly")))
 
+/* Read-only memory is marked before mark_rodata_ro() is called. */
+#define __ro_after_init __read_mostly
+
 #endif
diff --git a/arch/s390/include/uapi/asm/unistd.h b/arch/s390/include/uapi/asm/unistd.h
index ab3aa6875a59..4384bc797a54 100644
--- a/arch/s390/include/uapi/asm/unistd.h
+++ b/arch/s390/include/uapi/asm/unistd.h
@@ -311,7 +311,9 @@
 #define __NR_shutdown		373
 #define __NR_mlock2		374
 #define __NR_copy_file_range	375
-#define NR_syscalls 376
+#define __NR_preadv2		376
+#define __NR_pwritev2		377
+#define NR_syscalls 378
 
 /* 
  * There are some system calls that are not present on 64 bit, some
diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c
index 58bf4572d457..62f066b5259e 100644
--- a/arch/s390/kernel/perf_cpum_cf.c
+++ b/arch/s390/kernel/perf_cpum_cf.c
@@ -670,6 +670,7 @@ static int cpumf_pmu_notifier(struct notifier_block *self, unsigned long action,
 
 	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_ONLINE:
+	case CPU_DOWN_FAILED:
 		flags = PMC_INIT;
 		smp_call_function_single(cpu, setup_pmc_cpu, &flags, 1);
 		break;
diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c
index 1a43474df541..eaab9a7cb3be 100644
--- a/arch/s390/kernel/perf_cpum_sf.c
+++ b/arch/s390/kernel/perf_cpum_sf.c
@@ -1521,7 +1521,7 @@ static int cpumf_pmu_notifier(struct notifier_block *self,
 
 	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_ONLINE:
-	case CPU_ONLINE_FROZEN:
+	case CPU_DOWN_FAILED:
 		flags = PMC_INIT;
 		smp_call_function_single(cpu, setup_pmc_cpu, &flags, 1);
 		break;
diff --git a/arch/s390/kernel/syscalls.S b/arch/s390/kernel/syscalls.S
index 293d8b98fd52..9b59e6212d8f 100644
--- a/arch/s390/kernel/syscalls.S
+++ b/arch/s390/kernel/syscalls.S
@@ -384,3 +384,5 @@ SYSCALL(sys_recvmsg,compat_sys_recvmsg)
 SYSCALL(sys_shutdown,sys_shutdown)
 SYSCALL(sys_mlock2,compat_sys_mlock2)
 SYSCALL(sys_copy_file_range,compat_sys_copy_file_range) /* 375 */
+SYSCALL(sys_preadv2,compat_sys_preadv2)
+SYSCALL(sys_pwritev2,compat_sys_pwritev2)
diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c
index 49a1c84ed266..a8a6765f1a51 100644
--- a/arch/s390/mm/gup.c
+++ b/arch/s390/mm/gup.c
@@ -20,9 +20,9 @@
 static inline int gup_pte_range(pmd_t *pmdp, pmd_t pmd, unsigned long addr,
 		unsigned long end, int write, struct page **pages, int *nr)
 {
+	struct page *head, *page;
 	unsigned long mask;
 	pte_t *ptep, pte;
-	struct page *page;
 
 	mask = (write ? _PAGE_PROTECT : 0) | _PAGE_INVALID | _PAGE_SPECIAL;
 
@@ -37,12 +37,14 @@ static inline int gup_pte_range(pmd_t *pmdp, pmd_t pmd, unsigned long addr,
 			return 0;
 		VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
 		page = pte_page(pte);
-		if (!page_cache_get_speculative(page))
+		head = compound_head(page);
+		if (!page_cache_get_speculative(head))
 			return 0;
 		if (unlikely(pte_val(pte) != pte_val(*ptep))) {
-			put_page(page);
+			put_page(head);
 			return 0;
 		}
+		VM_BUG_ON_PAGE(compound_head(page) != head, page);
 		pages[*nr] = page;
 		(*nr)++;
 
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 73e290337092..c7b0451397d6 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -108,6 +108,13 @@ void __init paging_init(void)
 	free_area_init_nodes(max_zone_pfns);
 }
 
+void mark_rodata_ro(void)
+{
+	/* Text and rodata are already protected. Nothing to do here. */
+	pr_info("Write protecting the kernel read-only data: %luk\n",
+		((unsigned long)&_eshared - (unsigned long)&_stext) >> 10);
+}
+
 void __init mem_init(void)
 {
 	if (MACHINE_HAS_TLB_LC)
@@ -126,9 +133,6 @@ void __init mem_init(void)
 	setup_zero_pages();	/* Setup zeroed pages. */
 
 	mem_init_print_info(NULL);
-	printk("Write protected kernel read-only data: %#lx - %#lx\n",
-	       (unsigned long)&_stext,
-	       PFN_ALIGN((unsigned long)&_eshared) - 1);
 }
 
 void free_initmem(void)
diff --git a/arch/s390/pci/pci_clp.c b/arch/s390/pci/pci_clp.c
index 21591ddb4c1f..1a4512c8544a 100644
--- a/arch/s390/pci/pci_clp.c
+++ b/arch/s390/pci/pci_clp.c
@@ -176,8 +176,7 @@ static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh)
 		rc = clp_store_query_pci_fn(zdev, &rrb->response);
 		if (rc)
 			goto out;
-		if (rrb->response.pfgid)
-			rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
+		rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
 	} else {
 		zpci_err("Q PCI FN:\n");
 		zpci_err_clp(rrb->response.hdr.rsp, rc);