pm24.git/arch/powerpc/sysdev, branch v5.6

Merge tag 'powerpc-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2020-02-04T13:06:46Z

Pull powerpc updates from Michael Ellerman: "A pretty small batch for us, and apologies for it being a bit late, I wanted to sneak Christophe's user_access_begin() series in. Summary: - Implement user_access_begin() and friends for our platforms that support controlling kernel access to userspace. - Enable CONFIG_VMAP_STACK on 32-bit Book3S and 8xx. - Some tweaks to our pseries IOMMU code to allow SVMs ("secure" virtual machines) to use the IOMMU. - Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 32-bit VDSO, and some other improvements. - A series to use the PCI hotplug framework to control opencapi card's so that they can be reset and re-read after flashing a new FPGA image. As well as other minor fixes and improvements as usual. Thanks to: Alastair D'Silva, Alexandre Ghiti, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Bai Yingjie, Chen Zhou, Christophe Leroy, Frederic Barrat, Greg Kurz, Jason A. Donenfeld, Joel Stanley, Jordan Niethe, Julia Lawall, Krzysztof Kozlowski, Laurent Dufour, Laurentiu Tudor, Linus Walleij, Michael Bringmann, Nathan Chancellor, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Peter Ujfalusi, Pingfan Liu, Ram Pai, Randy Dunlap, Russell Currey, Sam Bobroff, Sebastian Andrzej Siewior, Shawn Anastasio, Stephen Rothwell, Steve Best, Sukadev Bhattiprolu, Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain" * tag 'powerpc-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (131 commits) powerpc: configs: Cleanup old Kconfig options powerpc/configs/skiroot: Enable some more hardening options powerpc/configs/skiroot: Disable xmon default & enable reboot on panic powerpc/configs/skiroot: Enable security features powerpc/configs/skiroot: Update for symbol movement only powerpc/configs/skiroot: Drop default n CONFIG_CRYPTO_ECHAINIV powerpc/configs/skiroot: Drop HID_LOGITECH powerpc/configs: Drop NET_VENDOR_HP which moved to staging powerpc/configs: NET_CADENCE became NET_VENDOR_CADENCE powerpc/configs: Drop CONFIG_QLGE which moved to staging powerpc: Do not consider weak unresolved symbol relocations as bad powerpc/32s: Fix kasan_early_hash_table() for CONFIG_VMAP_STACK powerpc: indent to improve Kconfig readability powerpc: Provide initial documentation for PAPR hcalls powerpc: Implement user_access_save() and user_access_restore() powerpc: Implement user_access_begin and friends powerpc/32s: Prepare prevent_user_access() for user_access_end() powerpc/32s: Drop NULL addr verification powerpc/kuap: Fix set direction in allow/prevent_user_access() powerpc/32s: Fix bad_kuap_fault() ...

powerpc: use probe_user_read() and probe_user_write()

2020-01-25T13:11:35Z

Instead of opencoding, use probe_user_read() to failessly read a user location and probe_user_write() for writing to user. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/e041f5eedb23f09ab553be8a91c3de2087147320.1579800517.git.christophe.leroy@c-s.fr

powerpc/xive: Discard ESB load value when interrupt is invalid

2020-01-22T09:31:41Z

A load on an ESB page returning all 1's means that the underlying device has invalidated the access to the PQ state of the interrupt through mmio. It may happen, for example when querying a PHB interrupt while the PHB is in an error state. In that case, we should consider the interrupt to be invalid when checking its state in the irq_get_irqchip_state() handler. Fixes: da15c03b047d ("powerpc/xive: Implement get_irqchip_state method for XIVE to fix shutdown race") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Frederic Barrat [clg: wrote a commit log, introduced XIVE_ESB_INVALID ] Signed-off-by: Cédric Le Goater Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200113130118.27969-1-clg@kaod.org

powerpc/mpic: constify copied structure

2020-01-07T10:42:16Z

The mpic_ipi_chip and mpic_irq_ht_chip structures are only copied into other structures, so make them const. The opportunity for this change was found using Coccinelle. Signed-off-by: Julia Lawall Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1577864614-5543-10-git-send-email-Julia.Lawall@inria.fr

powerpc/xive: Skip ioremap() of ESB pages for LSI interrupts

2019-12-04T13:11:45Z

The PCI INTx interrupts and other LSI interrupts are handled differently under a sPAPR platform. When the interrupt source characteristics are queried, the hypervisor returns an H_INT_ESB flag to inform the OS that it should be using the H_INT_ESB hcall for interrupt management and not loads and stores on the interrupt ESB pages. A default -1 value is returned for the addresses of the ESB pages. The driver ignores this condition today and performs a bogus IO mapping. Recent changes and the DEBUG_VM configuration option make the bug visible with : kernel BUG at arch/powerpc/include/asm/book3s/64/pgtable.h:612! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Radix MMU=Hash SMP NR_CPUS=1024 NUMA pSeries Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.4.0-0.rc6.git0.1.fc32.ppc64le #1 NIP: c000000000f63294 LR: c000000000f62e44 CTR: 0000000000000000 REGS: c0000000fa45f0d0 TRAP: 0700 Not tainted (5.4.0-0.rc6.git0.1.fc32.ppc64le) ... NIP ioremap_page_range+0x4c4/0x6e0 LR ioremap_page_range+0x74/0x6e0 Call Trace: ioremap_page_range+0x74/0x6e0 (unreliable) do_ioremap+0x8c/0x120 __ioremap_caller+0x128/0x140 ioremap+0x30/0x50 xive_spapr_populate_irq_data+0x170/0x260 xive_irq_domain_map+0x8c/0x170 irq_domain_associate+0xb4/0x2d0 irq_create_mapping+0x1e0/0x3b0 irq_create_fwspec_mapping+0x27c/0x3e0 irq_create_of_mapping+0x98/0xb0 of_irq_parse_and_map_pci+0x168/0x230 pcibios_setup_device+0x88/0x250 pcibios_setup_bus_devices+0x54/0x100 __of_scan_bus+0x160/0x310 pcibios_scan_phb+0x330/0x390 pcibios_init+0x8c/0x128 do_one_initcall+0x60/0x2c0 kernel_init_freeable+0x290/0x378 kernel_init+0x2c/0x148 ret_from_kernel_thread+0x5c/0x80 Fixes: bed81ee181dd ("powerpc/xive: introduce H_INT_ESB hcall") Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: Cédric Le Goater Tested-by: Daniel Axtens Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191203163642.2428-1-clg@kaod.org

Merge tag 'powerpc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2019-11-30T22:35:43Z

Pull powerpc updates from Michael Ellerman: "Highlights: - Infrastructure for secure boot on some bare metal Power9 machines. The firmware support is still in development, so the code here won't actually activate secure boot on any existing systems. - A change to xmon (our crash handler / pseudo-debugger) to restrict it to read-only mode when the kernel is lockdown'ed, otherwise it's trivial to drop into xmon and modify kernel data, such as the lockdown state. - Support for KASLR on 32-bit BookE machines (Freescale / NXP). - Fixes for our flush_icache_range() and __kernel_sync_dicache() (VDSO) to work with memory ranges >4GB. - Some reworks of the pseries CMM (Cooperative Memory Management) driver to make it behave more like other balloon drivers and enable some cleanups of generic mm code. - A series of fixes to our hardware breakpoint support to properly handle unaligned watchpoint addresses. Plus a bunch of other smaller improvements, fixes and cleanups. Thanks to: Alastair D'Silva, Andrew Donnellan, Aneesh Kumar K.V, Anthony Steinhauser, Cédric Le Goater, Chris Packham, Chris Smart, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens, David Hildenbrand, Deb McLemore, Diana Craciun, Eric Richter, Geert Uytterhoeven, Greg Kroah-Hartman, Greg Kurz, Gustavo L. F. Walbon, Hari Bathini, Harish, Jason Yan, Krzysztof Kozlowski, Leonardo Bras, Mathieu Malaterre, Mauro S. M. Rodrigues, Michal Suchanek, Mimi Zohar, Nathan Chancellor, Nathan Lynch, Nayna Jain, Nick Desaulniers, Oliver O'Halloran, Qian Cai, Rasmus Villemoes, Ravi Bangoria, Sam Bobroff, Santosh Sivaraj, Scott Wood, Thomas Huth, Tyrel Datwyler, Vaibhav Jain, Valentin Longchamp, YueHaibing" * tag 'powerpc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (144 commits) powerpc/fixmap: fix crash with HIGHMEM x86/efi: remove unused variables powerpc: Define arch_is_kernel_initmem_freed() for lockdep powerpc/prom_init: Use -ffreestanding to avoid a reference to bcmp powerpc: Avoid clang warnings around setjmp and longjmp powerpc: Don't add -mabi= flags when building with Clang powerpc: Fix Kconfig indentation powerpc/fixmap: don't clear fixmap area in paging_init() selftests/powerpc: spectre_v2 test must be built 64-bit powerpc/powernv: Disable native PCIe port management powerpc/kexec: Move kexec files into a dedicated subdir. powerpc/32: Split kexec low level code out of misc_32.S powerpc/sysdev: drop simple gpio powerpc/83xx: map IMMR with a BAT. powerpc/32s: automatically allocate BAT in setbat() powerpc/ioremap: warn on early use of ioremap() powerpc: Add support for GENERIC_EARLY_IOREMAP powerpc/fixmap: Use __fix_to_virt() instead of fix_to_virt() powerpc/8xx: use the fixmapped IMMR in cpm_reset() powerpc/8xx: add __init to cpm1 init functions ...

dma-mapping: treat dev->bus_dma_mask as a DMA limit

2019-11-21T17:14:35Z

Using a mask to represent bus DMA constraints has a set of limitations. The biggest one being it can only hold a power of two (minus one). The DMA mapping code is already aware of this and treats dev->bus_dma_mask as a limit. This quirk is already used by some architectures although still rare. With the introduction of the Raspberry Pi 4 we've found a new contender for the use of bus DMA limits, as its PCIe bus can only address the lower 3GB of memory (of a total of 4GB). This is impossible to represent with a mask. To make things worse the device-tree code rounds non power of two bus DMA limits to the next power of two, which is unacceptable in this case. In the light of this, rename dev->bus_dma_mask to dev->bus_dma_limit all over the tree and treat it as such. Note that dev->bus_dma_limit should contain the higher accessible DMA address. Signed-off-by: Nicolas Saenz Julienne Reviewed-by: Robin Murphy Signed-off-by: Christoph Hellwig

powerpc/sysdev: drop simple gpio

2019-11-21T04:41:34Z

There is a config item CONFIG_SIMPLE_GPIO which provides simple memory mapped GPIOs specific to powerpc. However, the only platform which selects this option is mpc5200, and this platform doesn't use it. There are three boards calling simple_gpiochip_init(), but as they don't select CONFIG_SIMPLE_GPIO, this is just a nop. Simple_gpio is just redundant with the generic MMIO GPIO driver which can be found in driver/gpio/ and selected via CONFIG_GPIO_GENERIC_PLATFORM, so drop simple_gpio driver. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/bf930402613b41b42d0441b784e0cc43fc18d1fb.1572529632.git.christophe.leroy@c-s.fr

powerpc/xive: Prevent page fault issues in the machine crash handler

2019-11-13T05:58:10Z

When the machine crash handler is invoked, all interrupts are masked but interrupts which have not been started yet do not have an ESB page mapped in the Linux address space. This crashes the 'crash kexec' sequence on sPAPR guests. To fix, force the mapping of the ESB page when an interrupt is being mapped in the Linux IRQ number space. This is done by setting the initial state of the interrupt to OFF which is not necessarily the case on PowerNV. Fixes: 243e25112d06 ("powerpc/xive: Native exploitation of the XIVE interrupt controller") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Cédric Le Goater Reviewed-by: Greg Kurz Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191031063100.3864-1-clg@kaod.org

KVM: PPC: Book3S HV: use smp_mb() when setting/clearing host_ipi flag

2019-09-24T02:46:26Z

On a 2-socket Power9 system with 32 cores/128 threads (SMT4) and 1TB of memory running the following guest configs: guest A: - 224GB of memory - 56 VCPUs (sockets=1,cores=28,threads=2), where: VCPUs 0-1 are pinned to CPUs 0-3, VCPUs 2-3 are pinned to CPUs 4-7, ... VCPUs 54-55 are pinned to CPUs 108-111 guest B: - 4GB of memory - 4 VCPUs (sockets=1,cores=4,threads=1) with the following workloads (with KSM and THP enabled in all): guest A: stress --cpu 40 --io 20 --vm 20 --vm-bytes 512M guest B: stress --cpu 4 --io 4 --vm 4 --vm-bytes 512M host: stress --cpu 4 --io 4 --vm 2 --vm-bytes 256M the below soft-lockup traces were observed after an hour or so and persisted until the host was reset (this was found to be reliably reproducible for this configuration, for kernels 4.15, 4.18, 5.0, and 5.3-rc5): [ 1253.183290] rcu: INFO: rcu_sched self-detected stall on CPU [ 1253.183319] rcu: 124-....: (5250 ticks this GP) idle=10a/1/0x4000000000000002 softirq=5408/5408 fqs=1941 [ 1256.287426] watchdog: BUG: soft lockup - CPU#105 stuck for 23s! [CPU 52/KVM:19709] [ 1264.075773] watchdog: BUG: soft lockup - CPU#24 stuck for 23s! [worker:19913] [ 1264.079769] watchdog: BUG: soft lockup - CPU#31 stuck for 23s! [worker:20331] [ 1264.095770] watchdog: BUG: soft lockup - CPU#45 stuck for 23s! [worker:20338] [ 1264.131773] watchdog: BUG: soft lockup - CPU#64 stuck for 23s! [avocado:19525] [ 1280.408480] watchdog: BUG: soft lockup - CPU#124 stuck for 22s! [ksmd:791] [ 1316.198012] rcu: INFO: rcu_sched self-detected stall on CPU [ 1316.198032] rcu: 124-....: (21003 ticks this GP) idle=10a/1/0x4000000000000002 softirq=5408/5408 fqs=8243 [ 1340.411024] watchdog: BUG: soft lockup - CPU#124 stuck for 22s! [ksmd:791] [ 1379.212609] rcu: INFO: rcu_sched self-detected stall on CPU [ 1379.212629] rcu: 124-....: (36756 ticks this GP) idle=10a/1/0x4000000000000002 softirq=5408/5408 fqs=14714 [ 1404.413615] watchdog: BUG: soft lockup - CPU#124 stuck for 22s! [ksmd:791] [ 1442.227095] rcu: INFO: rcu_sched self-detected stall on CPU [ 1442.227115] rcu: 124-....: (52509 ticks this GP) idle=10a/1/0x4000000000000002 softirq=5408/5408 fqs=21403 [ 1455.111787] INFO: task worker:19907 blocked for more than 120 seconds. [ 1455.111822] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.111833] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.111884] INFO: task worker:19908 blocked for more than 120 seconds. [ 1455.111905] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.111925] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.111966] INFO: task worker:20328 blocked for more than 120 seconds. [ 1455.111986] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.111998] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112048] INFO: task worker:20330 blocked for more than 120 seconds. [ 1455.112068] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.112097] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112138] INFO: task worker:20332 blocked for more than 120 seconds. [ 1455.112159] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.112179] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112210] INFO: task worker:20333 blocked for more than 120 seconds. [ 1455.112231] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.112242] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112282] INFO: task worker:20335 blocked for more than 120 seconds. [ 1455.112303] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.112332] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112372] INFO: task worker:20336 blocked for more than 120 seconds. [ 1455.112392] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 CPUs 45, 24, and 124 are stuck on spin locks, likely held by CPUs 105 and 31. CPUs 105 and 31 are stuck in smp_call_function_many(), waiting on target CPU 42. For instance: # CPU 105 registers (via xmon) R00 = c00000000020b20c R16 = 00007d1bcd800000 R01 = c00000363eaa7970 R17 = 0000000000000001 R02 = c0000000019b3a00 R18 = 000000000000006b R03 = 000000000000002a R19 = 00007d537d7aecf0 R04 = 000000000000002a R20 = 60000000000000e0 R05 = 000000000000002a R21 = 0801000000000080 R06 = c0002073fb0caa08 R22 = 0000000000000d60 R07 = c0000000019ddd78 R23 = 0000000000000001 R08 = 000000000000002a R24 = c00000000147a700 R09 = 0000000000000001 R25 = c0002073fb0ca908 R10 = c000008ffeb4e660 R26 = 0000000000000000 R11 = c0002073fb0ca900 R27 = c0000000019e2464 R12 = c000000000050790 R28 = c0000000000812b0 R13 = c000207fff623e00 R29 = c0002073fb0ca808 R14 = 00007d1bbee00000 R30 = c0002073fb0ca800 R15 = 00007d1bcd600000 R31 = 0000000000000800 pc = c00000000020b260 smp_call_function_many+0x3d0/0x460 cfar= c00000000020b270 smp_call_function_many+0x3e0/0x460 lr = c00000000020b20c smp_call_function_many+0x37c/0x460 msr = 900000010288b033 cr = 44024824 ctr = c000000000050790 xer = 0000000000000000 trap = 100 CPU 42 is running normally, doing VCPU work: # CPU 42 stack trace (via xmon) [link register ] c00800001be17188 kvmppc_book3s_radix_page_fault+0x90/0x2b0 [kvm_hv] [c000008ed3343820] c000008ed3343850 (unreliable) [c000008ed33438d0] c00800001be11b6c kvmppc_book3s_hv_page_fault+0x264/0xe30 [kvm_hv] [c000008ed33439d0] c00800001be0d7b4 kvmppc_vcpu_run_hv+0x8dc/0xb50 [kvm_hv] [c000008ed3343ae0] c00800001c10891c kvmppc_vcpu_run+0x34/0x48 [kvm] [c000008ed3343b00] c00800001c10475c kvm_arch_vcpu_ioctl_run+0x244/0x420 [kvm] [c000008ed3343b90] c00800001c0f5a78 kvm_vcpu_ioctl+0x470/0x7c8 [kvm] [c000008ed3343d00] c000000000475450 do_vfs_ioctl+0xe0/0xc70 [c000008ed3343db0] c0000000004760e4 ksys_ioctl+0x104/0x120 [c000008ed3343e00] c000000000476128 sys_ioctl+0x28/0x80 [c000008ed3343e20] c00000000000b388 system_call+0x5c/0x70 --- Exception: c00 (System Call) at 00007d545cfd7694 SP (7d53ff7edf50) is in userspace It was subsequently found that ipi_message[PPC_MSG_CALL_FUNCTION] was set for CPU 42 by at least 1 of the CPUs waiting in smp_call_function_many(), but somehow the corresponding call_single_queue entries were never processed by CPU 42, causing the callers to spin in csd_lock_wait() indefinitely. Nick Piggin suggested something similar to the following sequence as a possible explanation (interleaving of CALL_FUNCTION/RESCHEDULE IPI messages seems to be most common, but any mix of CALL_FUNCTION and !CALL_FUNCTION messages could trigger it): CPU X: smp_muxed_ipi_set_message(): X: smp_mb() X: message[RESCHEDULE] = 1 X: doorbell_global_ipi(42): X: kvmppc_set_host_ipi(42, 1) X: ppc_msgsnd_sync()/smp_mb() X: ppc_msgsnd() -> 42 42: doorbell_exception(): // from CPU X 42: ppc_msgsync() 105: smp_muxed_ipi_set_message(): 105: smb_mb() // STORE DEFERRED DUE TO RE-ORDERING --105: message[CALL_FUNCTION] = 1 | 105: doorbell_global_ipi(42): | 105: kvmppc_set_host_ipi(42, 1) | 42: kvmppc_set_host_ipi(42, 0) | 42: smp_ipi_demux_relaxed() | 42: // returns to executing guest | // RE-ORDERED STORE COMPLETES ->105: message[CALL_FUNCTION] = 1 105: ppc_msgsnd_sync()/smp_mb() 105: ppc_msgsnd() -> 42 42: local_paca->kvm_hstate.host_ipi == 0 // IPI ignored 105: // hangs waiting on 42 to process messages/call_single_queue This can be prevented with an smp_mb() at the beginning of kvmppc_set_host_ipi(), such that stores to message[] (or other state indicated by the host_ipi flag) are ordered vs. the store to to host_ipi. However, doing so might still allow for the following scenario (not yet observed): CPU X: smp_muxed_ipi_set_message(): X: smp_mb() X: message[RESCHEDULE] = 1 X: doorbell_global_ipi(42): X: kvmppc_set_host_ipi(42, 1) X: ppc_msgsnd_sync()/smp_mb() X: ppc_msgsnd() -> 42 42: doorbell_exception(): // from CPU X 42: ppc_msgsync() // STORE DEFERRED DUE TO RE-ORDERING -- 42: kvmppc_set_host_ipi(42, 0) | 42: smp_ipi_demux_relaxed() | 105: smp_muxed_ipi_set_message(): | 105: smb_mb() | 105: message[CALL_FUNCTION] = 1 | 105: doorbell_global_ipi(42): | 105: kvmppc_set_host_ipi(42, 1) | // RE-ORDERED STORE COMPLETES -> 42: kvmppc_set_host_ipi(42, 0) 42: // returns to executing guest 105: ppc_msgsnd_sync()/smp_mb() 105: ppc_msgsnd() -> 42 42: local_paca->kvm_hstate.host_ipi == 0 // IPI ignored 105: // hangs waiting on 42 to process messages/call_single_queue Fixing this scenario would require an smp_mb() *after* clearing host_ipi flag in kvmppc_set_host_ipi() to order the store vs. subsequent processing of IPI messages. To handle both cases, this patch splits kvmppc_set_host_ipi() into separate set/clear functions, where we execute smp_mb() prior to setting host_ipi flag, and after clearing host_ipi flag. These functions pair with each other to synchronize the sender and receiver sides. With that change in place the above workload ran for 20 hours without triggering any lock-ups. Fixes: 755563bc79c7 ("powerpc/powernv: Fixes for hypervisor doorbell handling") # v4.0 Signed-off-by: Michael Roth Acked-by: Paul Mackerras Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190911223155.16045-1-mdroth@linux.vnet.ibm.com