kernel.git/arch/powerpc/kexec, branch linux-6.14.y

powerpc/kexec: fix physical address calculation in clear_utlb_entry()

2025-04-10T12:44:19Z

[ Upstream commit 861efb8a48ee8b73ae4e8817509cd4e82fd52bc4 ] In relocate_32.S, function clear_utlb_entry() goes into real mode. To do so, it has to calculate the physical address based on the virtual address. To get the virtual address it uses 'bl' which is problematic (see commit c974809a26a1 ("powerpc/vdso: Avoid link stack corruption in __get_datapage()")). In addition, the calculation is done on a wrong address because 'bl' loads LR with the address of the following instruction, not the address of the target. So when the target is not the instruction following the 'bl' instruction, it may lead to unexpected behaviour. Fix it by re-writing the code so that is goes via another path which is based 'bcl 20,31,.+4' which is the right instruction to use for that. Fixes: 683430200315 ("powerpc/47x: Kernel support for KEXEC") Signed-off-by: Christophe Leroy Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/dc4f9616fba9c05c5dbf9b4b5480eb1c362adc17.1741256651.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin

kexec: Consolidate machine_kexec_mask_interrupts() implementation

2024-12-11T19:32:34Z

Consolidate the machine_kexec_mask_interrupts implementation into a common function located in a new file: kernel/irq/kexec.c. This removes duplicate implementations from architecture-specific files in arch/arm, arch/arm64, arch/powerpc, and arch/riscv, reducing code duplication and improving maintainability. The new implementation retains architecture-specific behavior for CONFIG_GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD, which was previously implemented for ARM64. When enabled (currently for ARM64), it clears the active state of interrupts forwarded to virtual machines (VMs) before handling other interrupt masking operations. Signed-off-by: Eliav Farber Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20241204142003.32859-2-farbere@amazon.com

powerpc/kexec: Fix return of uninitialized variable

2024-11-14T13:29:46Z

of_property_read_u64() can fail and leave the variable uninitialized, which will then be used. Return error if reading the property failed. Fixes: 2e6bd221d96f ("powerpc/kexec_file: Enable early kernel OPAL calls") Signed-off-by: Zhang Zekun Signed-off-by: Michael Ellerman Link: https://patch.msgid.link/20240930075628.125138-1-zhangzekun11@huawei.com

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

2024-07-20T04:00:33Z

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 ...

powerpc/kexec: Use of_property_read_reg()

2024-07-04T11:55:18Z

Replace open-coded parsing of "reg" property with of_property_read_reg(). Signed-off-by: Rob Herring (Arm) [mpe: Rename end to size, add comment to the bail out case] Signed-off-by: Michael Ellerman Link: https://msgid.link/20240702210344.722364-1-robh@kernel.org

powerpc/pseries: Fix scv instruction crash with kexec

2024-06-28T12:05:44Z

kexec on pseries disables AIL (reloc_on_exc), required for scv instruction support, before other CPUs have been shut down. This means they can execute scv instructions after AIL is disabled, which causes an interrupt at an unexpected entry location that crashes the kernel. Change the kexec sequence to disable AIL after other CPUs have been brought down. As a refresher, the real-mode scv interrupt vector is 0x17000, and the fixed-location head code probably couldn't easily deal with implementing such high addresses so it was just decided not to support that interrupt at all. Fixes: 7fa95f9adaee ("powerpc/64s: system call support for scv/rfscv instructions") Cc: stable@vger.kernel.org # v5.9+ Reported-by: Sourabh Jain Closes: https://lore.kernel.org/3b4b2943-49ad-4619-b195-bc416f1d1409@linux.ibm.com Signed-off-by: Nicholas Piggin Tested-by: Gautam Menghani Tested-by: Sourabh Jain Link: https://msgid.link/20240625134047.298759-1-npiggin@gmail.com Signed-off-by: Michael Ellerman

powerpc/kexec_file: fix cpus node update to FDT

2024-06-17T12:48:45Z

While updating the cpus node, commit 40c753993e3a ("powerpc/kexec_file: Use current CPU info while setting up FDT") first deletes all subnodes under the /cpus node. However, while adding sub-nodes back, it missed adding cpus subnodes whose device_type != "cpu", such as l2-cache*, l3-cache*, ibm,powerpc-cpu-features. Fix this by only deleting cpus sub-nodes of device_type == "cpus" and then adding all available nodes with device_type == "cpu". Fixes: 40c753993e3a ("powerpc/kexec_file: Use current CPU info while setting up FDT") Signed-off-by: Sourabh Jain Signed-off-by: Michael Ellerman Link: https://msgid.link/20240510102235.2269496-3-sourabhjain@linux.ibm.com

powerpc/kexec_file: fix extra size calculation for kexec FDT

2024-06-17T12:48:45Z

While setting up the FDT for kexec, CPU nodes that are added after the system boots and reserved memory ranges are incorporated into the initial_boot_params (base FDT). However, they are not taken into account when determining the additional size needed for the kexec FDT. As a result, kexec fails to load, generating the following error: [1116.774451] Error updating memory reserve map: FDT_ERR_NOSPACE kexec_file_load failed: No such process Therefore, consider the extra size for CPU nodes added post-system boot and reserved memory ranges while preparing the kexec FDT. While adding a new parameter to the setup_new_fdt_ppc64 function, it was noticed that there were a couple of unused parameters, so they were removed. Signed-off-by: Sourabh Jain Signed-off-by: Michael Ellerman Link: https://msgid.link/20240510102235.2269496-2-sourabhjain@linux.ibm.com

powerpc/crash: remove unnecessary NULL check before kvfree()

2024-05-03T02:20:50Z

Fix the following coccicheck build warning: arch/powerpc/kexec/crash.c:488:2-8: WARNING: NULL check before some freeing functions is not needed. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202404261048.skfV5DDB-lkp@intel.com/ Signed-off-by: Sourabh Jain Signed-off-by: Michael Ellerman Link: https://msgid.link/20240502182040.774759-1-sourabhjain@linux.ibm.com

powerpc/crash: add crash memory hotplug support

2024-04-23T05:00:04Z

Extend the arch crash hotplug handler, as introduced by the patch title ("powerpc: add crash CPU hotplug support"), to also support memory add/remove events. Elfcorehdr describes the memory of the crash kernel to capture the kernel; hence, it needs to be updated if memory resources change due to memory add/remove events. Therefore, arch_crash_handle_hotplug_event() is updated to recreate the elfcorehdr and replace it with the previous one on memory add/remove events. The memblock list is used to prepare the elfcorehdr. In the case of memory hot remove, the memblock list is updated after the arch crash hotplug handler is triggered, as depicted in Figure 1. Thus, the hot-removed memory is explicitly removed from the crash memory ranges to ensure that the memory ranges added to elfcorehdr do not include the hot-removed memory. Memory remove | v Offline pages | v Initiate memory notify call <----> crash hotplug handler chain for MEM_OFFLINE event | v Update memblock list Figure 1 There are two system calls, `kexec_file_load` and `kexec_load`, used to load the kdump image. A few changes have been made to ensure that the kernel can safely update the elfcorehdr component of the kdump image for both system calls. For the kexec_file_load syscall, kdump image is prepared in the kernel. To support an increasing number of memory regions, the elfcorehdr is built with extra buffer space to ensure that it can accommodate additional memory ranges in future. For the kexec_load syscall, the elfcorehdr is updated only if the KEXEC_CRASH_HOTPLUG_SUPPORT kexec flag is passed to the kernel by the kexec tool. Passing this flag to the kernel indicates that the elfcorehdr is built to accommodate additional memory ranges and the elfcorehdr segment is not considered for SHA calculation, making it safe to update. The changes related to this feature are kept under the CRASH_HOTPLUG config, and it is enabled by default. Signed-off-by: Sourabh Jain Acked-by: Hari Bathini Signed-off-by: Michael Ellerman Link: https://msgid.link/20240326055413.186534-7-sourabhjain@linux.ibm.com