Merge tag 'powerpc-6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Remove support for 40x CPUs & platforms

 - Add support to the 64-bit BPF JIT for cpu v4 instructions

 - Fix PCI hotplug driver crash on powernv

 - Fix doorbell emulation for KVM on PAPR guests (nestedv2)

 - Fix KVM nested guest handling of some less used SPRs

 - Online NUMA nodes with no CPU/memory if they have a PCI device
   attached

 - Reduce memory overhead of enabling kfence on 64-bit Radix MMU kernels

 - Reimplement the iommu table_group_ops for pseries for VFIO SPAPR TCE

Thanks to: Anjali K, Artem Savkov, Athira Rajeev, Breno Leitao, Brian
King, Celeste Liu, Christophe Leroy, Esben Haabendal, Gaurav Batra,
Gautam Menghani, Haren Myneni, Hari Bathini, Jeff Johnson, Krishna
Kumar, Krzysztof Kozlowski, Nathan Lynch, Nicholas Piggin, Nick Bowler,
Nilay Shroff, Rob Herring (Arm), Shawn Anastasio, Shivaprasad G Bhat,
Sourabh Jain, Srikar Dronamraju, Timothy Pearson, Uwe Kleine-König, and
Vaibhav Jain.

* tag 'powerpc-6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (57 commits)
  Documentation/powerpc: Mention 40x is removed
  powerpc: Remove 40x leftovers
  macintosh/therm_windtunnel: fix module unload.
  powerpc: Check only single values are passed to CPU/MMU feature checks
  powerpc/xmon: Fix disassembly CPU feature checks
  powerpc: Drop clang workaround for builtin constant checks
  powerpc64/bpf: jit support for signed division and modulo
  powerpc64/bpf: jit support for sign extended mov
  powerpc64/bpf: jit support for sign extended load
  powerpc64/bpf: jit support for unconditional byte swap
  powerpc64/bpf: jit support for 32bit offset jmp instruction
  powerpc/pci: Hotplug driver bridge support
  pci/hotplug/pnv_php: Fix hotplug driver crash on Powernv
  powerpc/configs: Update defconfig with now user-visible CONFIG_FSL_IFC
  powerpc: add missing MODULE_DESCRIPTION() macros
  macintosh/mac_hid: add MODULE_DESCRIPTION()
  KVM: PPC: add missing MODULE_DESCRIPTION() macros
  powerpc/kexec: Use of_property_read_reg()
  powerpc/64s/radix/kfence: map __kfence_pool at page granularity
  powerpc/pseries/iommu: Define spapr_tce_table_group_ops only with CONFIG_IOMMU_API
  ...

1 files changed, 21 insertions, 1 deletions

diff --git a/arch/powerpc/platforms/pseries/vas.c b/arch/powerpc/platforms/pseries/vas.c
index ba3fb7a7f2ea..c25eb1a38185 100644
--- a/arch/powerpc/platforms/pseries/vas.c
+++ b/arch/powerpc/platforms/pseries/vas.c
@@ -38,7 +38,27 @@ static long hcall_return_busy_check(long rc)
 {
 	/* Check if we are stalled for some time */
 	if (H_IS_LONG_BUSY(rc)) {
-		msleep(get_longbusy_msecs(rc));
+		unsigned int ms;
+		/*
+		 * Allocate, Modify and Deallocate HCALLs returns
+		 * H_LONG_BUSY_ORDER_1_MSEC or H_LONG_BUSY_ORDER_10_MSEC
+		 * for the long delay. So the sleep time should always
+		 * be either 1 or 10msecs, but in case if the HCALL
+		 * returns the long delay > 10 msecs, clamp the sleep
+		 * time to 10msecs.
+		 */
+		ms = clamp(get_longbusy_msecs(rc), 1, 10);
+
+		/*
+		 * msleep() will often sleep at least 20 msecs even
+		 * though the hypervisor suggests that the OS reissue
+		 * HCALLs after 1 or 10msecs. Also the delay hint from
+		 * the HCALL is just a suggestion. So OK to pause for
+		 * less time than the hinted delay. Use usleep_range()
+		 * to ensure we don't sleep much longer than actually
+		 * needed.
+		 */
+		usleep_range(ms * (USEC_PER_MSEC / 10), ms * USEC_PER_MSEC);
 		rc = H_BUSY;
 	} else if (rc == H_BUSY) {
 		cond_resched();