Linux kernel development work - see feature branches https://git.zx2c4.com/linux-dev/atom/arch/powerpc/platforms/pseries?h=master 2022-10-18T11:46:18Z 2022-10-18T11:46:18Z Haren Myneni haren@linux.ibm.com 2022-10-07T05:29:59Z urn:sha1:2147783d6bf0b7ca14c72a25527dc5135bd17f65 The hypervisor assigns VAS (Virtual Accelerator Switchboard) windows depends on cores configured in LPAR. The kernel uses OF reconfig notifier to reconfig VAS windows for DLPAR CPU event. In the case of shared CPU mode partition, the hypervisor assigns VAS windows depends on CPU entitled capacity, not based on vcpus. When the user changes CPU entitled capacity for the partition, drmgr uses /proc/ppc64/lparcfg interface to notify the kernel. This patch adds the following changes to update VAS resources for shared mode: - Call vas reconfig windows from lparcfg_write() - Ignore reconfig changes in the VAS notifier Signed-off-by: Haren Myneni <haren@linux.ibm.com> [mpe: Rework error handling, report any errors as EIO] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/efa9c16e4a78dda4567a16f13dabfd73cb4674a2.camel@linux.ibm.com 2022-10-18T11:46:18Z Haren Myneni haren@linux.ibm.com 2022-10-10T03:41:25Z urn:sha1:89ed0b769d6adf30364f60e6b1566961821a9893 irq_default_primary_handler() can be used only with IRQF_ONESHOT flag, but the flag disables IRQ before executing the thread handler and enables it after the interrupt is handled. But this IRQ disable sets the VAS IRQ OFF state in the hypervisor. In case if NX faults during this window, the hypervisor will not deliver the fault interrupt to the partition and the user space may wait continuously for the CSB update. So use VAS specific IRQ handler instead of calling the default primary handler. Increment pending_faults counter in IRQ handler and the bottom thread handler will process all faults based on this counter. In case if the another interrupt is received while the thread is running, it will be processed using this counter. The synchronization of top and bottom handlers will be done with IRQTF_RUNTHREAD flag and will re-enter to bottom half if this flag is set. Signed-off-by: Haren Myneni <haren@linux.ibm.com> Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/aaad8813b4762a6753cfcd0b605a7574a5192ec7.camel@linux.ibm.com 2022-10-13T11:30:07Z Nicholas Piggin npiggin@gmail.com 2022-10-13T07:31:31Z urn:sha1:90d5ce82e143b42b2fdfb95401a89f86b71cedb7 The recently moved dtl code must be compiled-in if CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y even if CONFIG_DTL=n. Fixes: 6ba5aa541aaa0 ("powerpc/pseries: Move dtl scanning and steal time accounting to pseries platform") Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20221013073131.1485742-1-npiggin@gmail.com 2022-09-30T08:35:53Z Michael Ellerman mpe@ellerman.id.au 2022-09-30T08:27:09Z urn:sha1:8535a1afff0f4f568eb589f3795a930ef3d483b0 Add firmware version details to the hardware description, which is printed at boot and in case of an oops. Use /hypervisor if we find it, though currently it only exists if we're running under qemu. Look for "ibm,powervm-partition" which is specified in PAPR+ v2.11 and tells us we're running under PowerVM. Failing that look for "ibm,fw-net-version" which is seen on PowerVM going back to at least Power6. eg: Hardware name: ... of:IBM,FW860.42 (SV860_138) hv:phyp Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220930082709.55830-6-mpe@ellerman.id.au 2022-09-30T08:35:51Z Haren Myneni haren@linux.ibm.com 2022-09-29T01:57:33Z urn:sha1:f3e5d9e53e74d77e711a2c90a91a8b0836a9e0b3 Generally the hypervisor decides to allocate a window on different VAS instances. But if user space wishes to allocate on the current VAS instance where the process is executing, the kernel has to pass associativity domain IDs to allocate VAS window HCALL. To determine the associativity domain IDs for the current CPU, smp_processor_id() is passed to node associativity HCALL which may return H_P2 (-55) error during DLPAR CPU event. This is because Linux CPU numbers (smp_processor_id()) are not the same as the hypervisor's view of CPU numbers. Fix the issue by passing hard_smp_processor_id() with VPHN_FLAG_VCPU flag (PAPR 14.11.6.1 H_HOME_NODE_ASSOCIATIVITY). Fixes: b22f2d88e435 ("powerpc/pseries/vas: Integrate API with open/close windows") Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Haren Myneni <haren@linux.ibm.com> [mpe: Update change log to mention Linux vs HV CPU numbers] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/55380253ea0c11341824cd4c0fc6bbcfc5752689.camel@linux.ibm.com 2022-09-28T09:22:14Z ye xingchen ye.xingchen@zte.com.cn 2022-08-25T07:26:57Z urn:sha1:91986d7f0300c2c01722e0eac5119bb0946fe9b5 Return the value vas_register_coproc_api() directly instead of storing it in another redundant variable. Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220825072657.229168-1-ye.xingchen@zte.com.cn 2022-09-28T09:22:14Z Nathan Lynch nathanl@linux.ibm.com 2022-09-26T13:16:42Z urn:sha1:99df7a2810b6d24651d4887ab61a142e042fb235 The /proc/powerpc/ofdt interface allows the root user to freely alter the in-kernel device tree, enabling arbitrary physical address writes via drivers that could bind to malicious device nodes, thus making it possible to disable lockdown. Historically this interface has been used on the pseries platform to facilitate the runtime addition and removal of processor, memory, and device resources (aka Dynamic Logical Partitioning or DLPAR). Years ago, the processor and memory use cases were migrated to designs that happen to be lockdown-friendly: device tree updates are communicated directly to the kernel from firmware without passing through untrusted user space. I/O device DLPAR via the "drmgr" command in powerpc-utils remains the sole legitimate user of /proc/powerpc/ofdt, but it is already broken in lockdown since it uses /dev/mem to allocate argument buffers for the rtas syscall. So only illegitimate uses of the interface should see a behavior change when running on a locked down kernel. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Acked-by: Paul Moore <paul@paul-moore.com> (LSM) Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220926131643.146502-2-nathanl@linux.ibm.com 2022-09-28T09:22:12Z Haren Myneni haren@linux.ibm.com 2022-09-22T08:27:07Z urn:sha1:465dda9d320d1cb9424f1015b0520ec4c4f0d279 When the migration is initiated, the hypervisor changes VAS mappings as part of pre-migration event. Then the OS gets the migration event which closes all VAS windows before the migration starts. NX generates continuous faults until windows are closed and the user space can not differentiate these NX faults coming from the actual migration. So to reduce this time window, close VAS windows first in pseries_migrate_partition(). Signed-off-by: Haren Myneni <haren@linux.ibm.com> Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/d8efade91dda831c9ed4abb226dab627da594c5f.camel@linux.ibm.com 2022-09-26T10:57:42Z Nicholas Piggin npiggin@gmail.com 2022-09-26T05:38:23Z urn:sha1:9a10ccb29c0a2befa5a9f691ed0ae37ee3e799a8 The .toc section is not really intended for arbitrary data. Writable data in particular prevents making the TOC read-only after relocation. Move hcall_tracepoint_refcount into the .data section. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220926053823.2668799-1-npiggin@gmail.com 2022-09-23T14:40:14Z Michael Ellerman mpe@ellerman.id.au 2022-09-23T14:40:14Z urn:sha1:ec5c3a359cfaf68d4db30969745db18f9928aab9 Merge our fixes branch to bring in a few things that new feature patches rely on or conflict with.