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

Pull s390 updates from Heiko Carstens:
 "Since Martin is on vacation you get the s390 pull request for the
  v4.15 merge window this time from me.

  Besides a lot of cleanups and bug fixes these are the most important
  changes:

   - a new regset for runtime instrumentation registers

   - hardware accelerated AES-GCM support for the aes_s390 module

   - support for the new CEX6S crypto cards

   - support for FORTIFY_SOURCE

   - addition of missing z13 and new z14 instructions to the in-kernel
     disassembler

   - generate opcode tables for the in-kernel disassembler out of a
     simple text file instead of having to manually maintain those
     tables

   - fast memset16, memset32 and memset64 implementations

   - removal of named saved segment support

   - hardware counter support for z14

   - queued spinlocks and queued rwlocks implementations for s390

   - use the stack_depth tracking feature for s390 BPF JIT

   - a new s390_sthyi system call which emulates the sthyi (store
     hypervisor information) instruction

   - removal of the old KVM virtio transport

   - an s390 specific CPU alternatives implementation which is used in
     the new spinlock code"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (88 commits)
  MAINTAINERS: add virtio-ccw.h to virtio/s390 section
  s390/noexec: execute kexec datamover without DAT
  s390: fix transactional execution control register handling
  s390/bpf: take advantage of stack_depth tracking
  s390: simplify transactional execution elf hwcap handling
  s390/zcrypt: Rework struct ap_qact_ap_info.
  s390/virtio: remove unused header file kvm_virtio.h
  s390: avoid undefined behaviour
  s390/disassembler: generate opcode tables from text file
  s390/disassembler: remove insn_to_mnemonic()
  s390/dasd: avoid calling do_gettimeofday()
  s390: vfio-ccw: Do not attempt to free no-op, test and tic cda.
  s390: remove named saved segment support
  s390/archrandom: Reconsider s390 arch random implementation
  s390/pci: do not require AIS facility
  s390/qdio: sanitize put_indicator
  s390/qdio: use atomic_cmpxchg
  s390/nmi: avoid using long-displacement facility
  s390: pass endianness info to sparse
  s390/decompressor: remove informational messages
  ...

1 files changed, 10 insertions, 12 deletions

diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c
index b0ba2c26b45e..a80050bbe2e4 100644
--- a/arch/s390/kernel/machine_kexec.c
+++ b/arch/s390/kernel/machine_kexec.c
@@ -106,7 +106,7 @@ static void __do_machine_kdump(void *image)
 static noinline void __machine_kdump(void *image)
 {
 	struct mcesa *mcesa;
-	unsigned long cr2_old, cr2_new;
+	union ctlreg2 cr2_old, cr2_new;
 	int this_cpu, cpu;
 
 	lgr_info_log();
@@ -123,11 +123,12 @@ static noinline void __machine_kdump(void *image)
 	if (MACHINE_HAS_VX)
 		save_vx_regs((__vector128 *) mcesa->vector_save_area);
 	if (MACHINE_HAS_GS) {
-		__ctl_store(cr2_old, 2, 2);
-		cr2_new = cr2_old | (1UL << 4);
-		__ctl_load(cr2_new, 2, 2);
+		__ctl_store(cr2_old.val, 2, 2);
+		cr2_new = cr2_old;
+		cr2_new.gse = 1;
+		__ctl_load(cr2_new.val, 2, 2);
 		save_gs_cb((struct gs_cb *) mcesa->guarded_storage_save_area);
-		__ctl_load(cr2_old, 2, 2);
+		__ctl_load(cr2_old.val, 2, 2);
 	}
 	/*
 	 * To create a good backchain for this CPU in the dump store_status
@@ -145,7 +146,7 @@ static noinline void __machine_kdump(void *image)
 /*
  * Check if kdump checksums are valid: We call purgatory with parameter "0"
  */
-static int kdump_csum_valid(struct kimage *image)
+static bool kdump_csum_valid(struct kimage *image)
 {
 #ifdef CONFIG_CRASH_DUMP
 	int (*start_kdump)(int) = (void *)image->start;
@@ -154,9 +155,9 @@ static int kdump_csum_valid(struct kimage *image)
 	__arch_local_irq_stnsm(0xfb); /* disable DAT */
 	rc = start_kdump(0);
 	__arch_local_irq_stosm(0x04); /* enable DAT */
-	return rc ? 0 : -EINVAL;
+	return rc == 0;
 #else
-	return -EINVAL;
+	return false;
 #endif
 }
 
@@ -219,10 +220,6 @@ int machine_kexec_prepare(struct kimage *image)
 {
 	void *reboot_code_buffer;
 
-	/* Can't replace kernel image since it is read-only. */
-	if (ipl_flags & IPL_NSS_VALID)
-		return -EOPNOTSUPP;
-
 	if (image->type == KEXEC_TYPE_CRASH)
 		return machine_kexec_prepare_kdump();
 
@@ -269,6 +266,7 @@ static void __do_machine_kexec(void *data)
 	s390_reset_system();
 	data_mover = (relocate_kernel_t) page_to_phys(image->control_code_page);
 
+	__arch_local_irq_stnsm(0xfb); /* disable DAT - avoid no-execute */
 	/* Call the moving routine */
 	(*data_mover)(&image->head, image->start);