Merge tag 's390-6.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Alexander Gordeev:

 - Add machine variable capacity information to /proc/sysinfo.

 - Limit the waste of page tables and always align vmalloc area size and
   base address on segment boundary.

 - Fix a memory leak when an attempt to register interruption sub class
   (ISC) for the adjunct-processor (AP) guest failed.

 - Reset response code AP_RESPONSE_INVALID_GISA to understandable by
   guest AP_RESPONSE_INVALID_ADDRESS in response to a failed
   interruption sub class (ISC) registration attempt.

 - Improve reaction to adjunct-processor (AP)
   AP_RESPONSE_OTHERWISE_CHANGED response code when enabling interrupts
   on behalf of a guest.

 - Fix incorrect sysfs 'status' attribute of adjunct-processor (AP)
   queue device bound to the vfio_ap device driver when the mediated
   device is attached to a guest, but the queue device is not passed
   through.

 - Rework struct ap_card to hold the whole adjunct-processor (AP) card
   hardware information. As result, all the ugly bit checks are replaced
   by simple evaluations of the required bit fields.

 - Improve handling of some weird scenarios between service element (SE)
   host and SE guest with adjunct-processor (AP) pass-through support.

 - Change local_ctl_set_bit() and local_ctl_clear_bit() so they return
   the previous value of the to be changed control register. This is
   useful if a bit is only changed temporarily and the previous content
   needs to be restored.

 - The kernel starts with machine checks disabled and is expected to
   enable it once trap_init() is called. However the implementation
   allows machine checks early. Consistently enable it in trap_init()
   only.

 - local_mcck_disable() and local_mcck_enable() assume that machine
   checks are always enabled. Instead implement and use
   local_mcck_save() and local_mcck_restore() to disable machine checks
   and restore the previous state.

 - Modification of floating point control (FPC) register of a traced
   process using ptrace interface may lead to corruption of the FPC
   register of the tracing process. Fix this.

 - kvm_arch_vcpu_ioctl_set_fpu() allows to set the floating point
   control (FPC) register in vCPU, but may lead to corruption of the FPC
   register of the host process. Fix this.

 - Use READ_ONCE() to read a vCPU floating point register value from the
   memory mapped area. This avoids that, depending on code generation, a
   different value is tested for validity than the one that is used.

 - Get rid of test_fp_ctl(), since it is quite subtle to use it
   correctly. Instead copy a new floating point control register value
   into its save area and test the validity of the new value when
   loading it.

 - Remove superfluous save_fpu_regs() call.

 - Remove s390 support for ARCH_WANTS_DYNAMIC_TASK_STRUCT. All machines
   provide the vector facility since many years and the need to make the
   task structure size dependent on the vector facility does not exist.

 - Remove the "novx" kernel command line option, as the vector code runs
   without any problems since many years.

 - Add the vector facility to the z13 architecture level set (ALS). All
   hypervisors support the vector facility since many years. This allows
   compile time optimizations of the kernel.

 - Get rid of MACHINE_HAS_VX and replace it with cpu_has_vx(). As
   result, the compiled code will have less runtime checks and less
   code.

 - Convert pgste_get_lock() and pgste_set_unlock() ASM inlines to C.

 - Convert the struct subchannel spinlock from pointer to member.

* tag 's390-6.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (24 commits)
  Revert "s390: update defconfigs"
  s390/cio: make sch->lock spinlock pointer a member
  s390: update defconfigs
  s390/mm: convert pgste locking functions to C
  s390/fpu: get rid of MACHINE_HAS_VX
  s390/als: add vector facility to z13 architecture level set
  s390/fpu: remove "novx" option
  s390/fpu: remove ARCH_WANTS_DYNAMIC_TASK_STRUCT support
  KVM: s390: remove superfluous save_fpu_regs() call
  s390/fpu: get rid of test_fp_ctl()
  KVM: s390: use READ_ONCE() to read fpc register value
  KVM: s390: fix setting of fpc register
  s390/ptrace: handle setting of fpc register correctly
  s390/nmi: implement and use local_mcck_save() / local_mcck_restore()
  s390/nmi: consistently enable machine checks in trap_init()
  s390/ctlreg: return old register contents when changing bits
  s390/ap: handle outband SE bind state change
  s390/ap: store TAPQ hwinfo in struct ap_card
  s390/vfio-ap: fix sysfs status attribute for AP queue devices
  s390/vfio-ap: improve reaction to response code 07 from PQAP(AQIC) command
  ...

1 files changed, 26 insertions, 8 deletions

diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index c15eadbb9983..c0b6e74d899a 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -184,11 +184,7 @@ struct thread_struct {
 	struct gs_cb *gs_cb;			/* Current guarded storage cb */
 	struct gs_cb *gs_bc_cb;			/* Broadcast guarded storage cb */
 	struct pgm_tdb trap_tdb;		/* Transaction abort diagnose block */
-	/*
-	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
-	 * the end.
-	 */
-	struct fpu fpu;			/* FP and VX register save area */
+	struct fpu fpu;				/* FP and VX register save area */
 };
 
 /* Flag to disable transactions. */
@@ -331,14 +327,36 @@ static inline unsigned long __extract_psw(void)
 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
 }
 
-static inline void local_mcck_enable(void)
+static inline unsigned long __local_mcck_save(void)
 {
-	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
+	unsigned long mask = __extract_psw();
+
+	__load_psw_mask(mask & ~PSW_MASK_MCHECK);
+	return mask & PSW_MASK_MCHECK;
+}
+
+#define local_mcck_save(mflags)			\
+do {						\
+	typecheck(unsigned long, mflags);	\
+	mflags = __local_mcck_save();		\
+} while (0)
+
+static inline void local_mcck_restore(unsigned long mflags)
+{
+	unsigned long mask = __extract_psw();
+
+	mask &= ~PSW_MASK_MCHECK;
+	__load_psw_mask(mask | mflags);
 }
 
 static inline void local_mcck_disable(void)
 {
-	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
+	__local_mcck_save();
+}
+
+static inline void local_mcck_enable(void)
+{
+	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
 }
 
 /*