s390 updates for 6.4-rc6

- Avoid linker error for randomly generated config file that
   has CONFIG_BRANCH_PROFILE_NONE enabled and make it similar
   to riscv, x86 and also to commit 4bf3ec384e ("s390: disable
   branch profiling for vdso").
 
 - Currently, if the device is offline and all the channel paths are
   either configured or varied offline, the associated subchannel gets
   unregistered. Don't unregister the subchannel, instead unregister
   offline device.
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Merge tag 's390-6.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Alexander Gordeev:

 - Avoid linker error for randomly generated config file that has
   CONFIG_BRANCH_PROFILE_NONE enabled and make it similar to riscv, x86
   and also to commit 4bf3ec384e ("s390: disable branch profiling for
   vdso").

 - Currently, if the device is offline and all the channel paths are
   either configured or varied offline, the associated subchannel gets
   unregistered. Don't unregister the subchannel, instead unregister
   offline device.

* tag 's390-6.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/purgatory: disable branch profiling
  s390/cio: unregister device when the only path is gone

arch/s390/purgatory/Makefile

@@ -26,6 +26,7 @@ KBUILD_CFLAGS += -Wno-pointer-sign -Wno-sign-compare
 KBUILD_CFLAGS += -fno-zero-initialized-in-bss -fno-builtin -ffreestanding
 KBUILD_CFLAGS += -Os -m64 -msoft-float -fno-common
 KBUILD_CFLAGS += -fno-stack-protector
+KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
 KBUILD_CFLAGS += $(CLANG_FLAGS)
 KBUILD_CFLAGS += $(call cc-option,-fno-PIE)
 KBUILD_AFLAGS := $(filter-out -DCC_USING_EXPOLINE,$(KBUILD_AFLAGS))

drivers/s390/cio/device.c

@@ -1376,6 +1376,7 @@ void ccw_device_set_notoper(struct ccw_device *cdev)
 enum io_sch_action {
 	IO_SCH_UNREG,
 	IO_SCH_ORPH_UNREG,
+	IO_SCH_UNREG_CDEV,
 	IO_SCH_ATTACH,
 	IO_SCH_UNREG_ATTACH,
 	IO_SCH_ORPH_ATTACH,
@@ -1408,7 +1409,7 @@ static enum io_sch_action sch_get_action(struct subchannel *sch)
 	}
 	if ((sch->schib.pmcw.pam & sch->opm) == 0) {
 		if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
-			return IO_SCH_UNREG;
+			return IO_SCH_UNREG_CDEV;
 		return IO_SCH_DISC;
 	}
 	if (device_is_disconnected(cdev))
@@ -1470,6 +1471,7 @@ static int io_subchannel_sch_event(struct subchannel *sch, int process)
 	case IO_SCH_ORPH_ATTACH:
 		ccw_device_set_disconnected(cdev);
 		break;
+	case IO_SCH_UNREG_CDEV:
 	case IO_SCH_UNREG_ATTACH:
 	case IO_SCH_UNREG:
 		if (!cdev)
@@ -1503,6 +1505,7 @@ static int io_subchannel_sch_event(struct subchannel *sch, int process)
 		if (rc)
 			goto out;
 		break;
+	case IO_SCH_UNREG_CDEV:
 	case IO_SCH_UNREG_ATTACH:
 		spin_lock_irqsave(sch->lock, flags);
 		sch_set_cdev(sch, NULL);