wireguard-linux/arch/powerpc/platforms/pseries/hotplug-cpu.c, branch jd/unified-crypt-queue

powerpc/pseries: Add cpu DLPAR support for drc-info property

2019-11-13T05:57:57Z

Older firmwares provided information about Dynamic Reconfig Connectors (DRC) through several device tree properties, namely ibm,drc-types, ibm,drc-indexes, ibm,drc-names, and ibm,drc-power-domains. New firmwares have the ability to present this same information in a much condensed format through a device tree property called ibm,drc-info. The existing cpu DLPAR hotplug code only understands the older DRC property format when validating the drc-index of a cpu during a hotplug add. This updates those code paths to use the ibm,drc-info property, when present, instead for validation. Signed-off-by: Tyrel Datwyler Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1573449697-5448-4-git-send-email-tyreld@linux.ibm.com

powerpc/pseries: safely roll back failed DLPAR cpu add

2019-11-05T00:26:45Z

dlpar_online_cpu() attempts to online all threads of a core that has been added to an LPAR. If onlining a non-primary thread fails (e.g. due to an allocation failure), the core is left with at least one thread online. dlpar_cpu_add() attempts to roll back the whole operation, releasing the core back to the platform. However, since some threads of the core being removed are still online, the BUG_ON(cpu_online(cpu)) in pseries_remove_processor() strikes: LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: CPU: 3 PID: 8587 Comm: drmgr Not tainted 5.3.0-rc2-00190-g9b123d1ea237-dirty #46 NIP: c0000000000eeb2c LR: c0000000000eeac4 CTR: c0000000000ee9e0 REGS: c0000001f745b6c0 TRAP: 0700 Not tainted (5.3.0-rc2-00190-g9b123d1ea237-dirty) MSR: 800000010282b033 CR: 44002448 XER: 00000000 CFAR: c00000000195d718 IRQMASK: 0 GPR00: c0000000000eeac4 c0000001f745b950 c0000000032f6200 0000000000000008 GPR04: 0000000000000008 c000000003349c78 0000000000000040 00000000000001ff GPR08: 0000000000000008 0000000000000000 0000000000000001 0007ffffffffffff GPR12: 0000000084002844 c00000001ecacb80 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000008 GPR24: c000000003349ee0 c00000000334a2e4 c0000000fca4d7a8 c000000001d20048 GPR28: 0000000000000001 ffffffffffffffff ffffffffffffffff c0000000fca4d7c4 NIP [c0000000000eeb2c] pseries_smp_notifier+0x14c/0x2e0 LR [c0000000000eeac4] pseries_smp_notifier+0xe4/0x2e0 Call Trace: [c0000001f745b950] [c0000000000eeac4] pseries_smp_notifier+0xe4/0x2e0 (unreliable) [c0000001f745ba10] [c0000000001ac774] notifier_call_chain+0xb4/0x190 [c0000001f745bab0] [c0000000001ad62c] blocking_notifier_call_chain+0x7c/0xb0 [c0000001f745baf0] [c00000000167bda0] of_detach_node+0xc0/0x110 [c0000001f745bb50] [c0000000000e7ae4] dlpar_detach_node+0x64/0xa0 [c0000001f745bb80] [c0000000000edefc] dlpar_cpu_add+0x31c/0x360 [c0000001f745bc10] [c0000000000ee980] dlpar_cpu_probe+0x50/0xb0 [c0000001f745bc50] [c00000000002cf70] arch_cpu_probe+0x40/0x70 [c0000001f745bc70] [c000000000ccd808] cpu_probe_store+0x48/0x80 [c0000001f745bcb0] [c000000000cbcef8] dev_attr_store+0x38/0x60 [c0000001f745bcd0] [c00000000059c980] sysfs_kf_write+0x70/0xb0 [c0000001f745bd10] [c00000000059afb8] kernfs_fop_write+0xf8/0x280 [c0000001f745bd60] [c0000000004b437c] __vfs_write+0x3c/0x70 [c0000001f745bd80] [c0000000004b8710] vfs_write+0xd0/0x220 [c0000001f745bdd0] [c0000000004b8acc] ksys_write+0x7c/0x140 [c0000001f745be20] [c00000000000bbd8] system_call+0x5c/0x68 Move dlpar_offline_cpu() up in the file so that dlpar_online_cpu() can use it to re-offline any threads that have been onlined when an error is encountered. Signed-off-by: Nathan Lynch Fixes: e666ae0b10aa ("powerpc/pseries: Update CPU hotplug error recovery") Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191016183611.10867-3-nathanl@linux.ibm.com

powerpc/pseries: address checkpatch warnings in dlpar_offline_cpu

2019-11-05T00:26:45Z

Remove some stray blank lines, convert a printk to pr_warn, and address a line length violation. One functional change: use WARN_ON instead of BUG_ON in case H_PROD of a ceded thread yields an unexpected result from the platform. We can expect this code path to get uninterruptibly stuck in __cpu_die() if this happens, but that's more desirable than crashing. Signed-off-by: Nathan Lynch Fixes: b6db63d1a7f0 ("pseries/pseries: Add code to online/offline CPUs of a DLPAR node") Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191016183611.10867-2-nathanl@linux.ibm.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Perform full re-add of CPU for topology update post-migration

2019-01-30T12:28:56Z

On pseries systems, performing a partition migration can result in altering the nodes a CPU is assigned to on the destination system. For exampl, pre-migration on the source system CPUs are in node 1 and 3, post-migration on the destination system CPUs are in nodes 2 and 3. Handling the node change for a CPU can cause corruption in the slab cache if we hit a timing where a CPUs node is changed while cache_reap() is invoked. The corruption occurs because the slab cache code appears to rely on the CPU and slab cache pages being on the same node. The current dynamic updating of a CPUs node done in arch/powerpc/mm/numa.c does not prevent us from hitting this scenario. Changing the device tree property update notification handler that recognizes an affinity change for a CPU to do a full DLPAR remove and add of the CPU instead of dynamically changing its node resolves this issue. Signed-off-by: Nathan Fontenot Signed-off-by: Michael W. Bringmann Tested-by: Michael W. Bringmann Signed-off-by: Michael Ellerman

powerpc: Convert to using %pOFn instead of device_node.name

2018-10-03T05:40:01Z

In preparation to remove the node name pointer from struct device_node, convert printf users to use the %pOFn format specifier. Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Arnd Bergmann Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Rob Herring Signed-off-by: Michael Ellerman

Merge branch 'topic/paca' into next

2018-03-30T22:09:36Z

Bring in yet another series that touches KVM code, and might need to be merged into the kvm-ppc branch to resolve conflicts. This required some changes in pnv_power9_force_smt4_catch/release() due to the paca array becomming an array of pointers.

powerpc/64: Use array of paca pointers and allocate pacas individually

2018-03-30T12:34:23Z

Change the paca array into an array of pointers to pacas. Allocate pacas individually. This allows flexibility in where the PACAs are allocated. Future work will allocate them node-local. Platforms that don't have address limits on PACAs would be able to defer PACA allocations until later in boot rather than allocate all possible ones up-front then freeing unused. This is slightly more overhead (one additional indirection) for cross CPU paca references, but those aren't too common. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/pseries: Fix build break for SPLPAR=n and CPU hotplug

2018-02-13T11:38:39Z

Commit e67e02a544e9 ("powerpc/pseries: Fix cpu hotplug crash with memoryless nodes") adds an unconditional call to find_and_online_cpu_nid(), which is only declared if CONFIG_PPC_SPLPAR is enabled. This results in the following build error if this is not the case. arch/powerpc/platforms/pseries/hotplug-cpu.o: In function `dlpar_online_cpu': arch/powerpc/platforms/pseries/hotplug-cpu.c:369: undefined reference to `.find_and_online_cpu_nid' Follow the guideline provided by similar functions and provide a dummy function if CONFIG_PPC_SPLPAR is not enabled. This also moves the external function declaration into an include file where it should be. Fixes: e67e02a544e9 ("powerpc/pseries: Fix cpu hotplug crash with memoryless nodes") Signed-off-by: Guenter Roeck [mpe: Change subject to emphasise the build fix] Signed-off-by: Michael Ellerman

powerpc/numa: Invalidate numa_cpu_lookup_table on cpu remove

2018-02-08T12:56:10Z

When DLPAR removing a CPU, the unmapping of the cpu from a node in unmap_cpu_from_node() should also invalidate the CPUs entry in the numa_cpu_lookup_table. There is not a guarantee that on a subsequent DLPAR add of the CPU the associativity will be the same and thus could be in a different node. Invalidating the entry in the numa_cpu_lookup_table causes the associativity to be read from the device tree at the time of the add. The current behavior of not invalidating the CPUs entry in the numa_cpu_lookup_table can result in scenarios where the the topology layout of CPUs in the partition does not match the device tree or the topology reported by the HMC. This bug looks like it was introduced in 2004 in the commit titled "ppc64: cpu hotplug notifier for numa", which is 6b15e4e87e32 in the linux-fullhist tree. Hence tag it for all stable releases. Cc: stable@vger.kernel.org Signed-off-by: Nathan Fontenot Reviewed-by: Tyrel Datwyler Signed-off-by: Michael Ellerman