kernel/arch/powerpc/kexec/file_load_64.c, branch linux-6.2.y

powerpc/kexec_file: fix implicit decl error

2023-02-06T11:00:30Z

kexec (PPC64) code calls memory_hotplug_max(). Add the header declaration for it from . Using does not work since the #include for depends on CONFIG_NUMA=y, which is not always set. Fixes this build error/warning: arch/powerpc/kexec/file_load_64.c: In function 'kexec_extra_fdt_size_ppc64': arch/powerpc/kexec/file_load_64.c:993:33: error: implicit declaration of function 'memory_hotplug_max' 993 | usm_entries = ((memory_hotplug_max() / drmem_lmb_size()) + | ^~~~~~~~~~~~~~~~~~ Fixes: fc546faa5595 ("powerpc/kexec_file: Count hot-pluggable memory in FDT estimate") Signed-off-by: Randy Dunlap Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230204172206.7662-1-rdunlap@infradead.org

powerpc/kexec_file: Count hot-pluggable memory in FDT estimate

2023-02-01T02:04:40Z

On Systems where online memory is lesser compared to max memory, the kexec_file_load system call may fail to load the kdump kernel with the below errors: "Failed to update fdt with linux,drconf-usable-memory property" "Error setting up usable-memory property for kdump kernel" This happens because the size estimation for usable memory properties for the kdump kernel's FDT is based on the online memory whereas the usable memory properties include max memory. In short, the hot-pluggable memory is not accounted for while estimating the size of the usable memory properties. The issue is addressed by calculating usable memory property size using max hotplug address instead of the last online memory address. Fixes: 2377c92e37fe ("powerpc/kexec_file: fix FDT size estimation for kdump kernel") Signed-off-by: Sourabh Jain Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230131030615.729894-1-sourabhjain@linux.ibm.com

powerpc/kexec_file: Fix division by zero in extra size estimation

2023-01-31T10:37:36Z

In kexec_extra_fdt_size_ppc64() there's logic to estimate how much extra space will be needed in the device tree for some memory related properties. That logic uses the size of RAM divided by drmem_lmb_size() to do the estimation. However drmem_lmb_size() can be zero if the machine has no hotpluggable memory configured, which is the case when booting with qemu and no maxmem=x parameter is passed (the default). The division by zero is reported by UBSAN, and can also lead to an overflow and a warning from kvmalloc, and kdump kernel loading fails: WARNING: CPU: 0 PID: 133 at mm/util.c:596 kvmalloc_node+0x15c/0x160 Modules linked in: CPU: 0 PID: 133 Comm: kexec Not tainted 6.2.0-rc5-03455-g07358bd97810 #223 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1200 0xf000005 of:SLOF,git-dd0dca pSeries NIP: c00000000041ff4c LR: c00000000041fe58 CTR: 0000000000000000 REGS: c0000000096ef750 TRAP: 0700 Not tainted (6.2.0-rc5-03455-g07358bd97810) MSR: 800000000282b033 CR: 24248242 XER: 2004011e CFAR: c00000000041fed0 IRQMASK: 0 ... NIP kvmalloc_node+0x15c/0x160 LR kvmalloc_node+0x68/0x160 Call Trace: kvmalloc_node+0x68/0x160 (unreliable) of_kexec_alloc_and_setup_fdt+0xb8/0x7d0 elf64_load+0x25c/0x4a0 kexec_image_load_default+0x58/0x80 sys_kexec_file_load+0x5c0/0x920 system_call_exception+0x128/0x330 system_call_vectored_common+0x15c/0x2ec To fix it, skip the calculation if drmem_lmb_size() is zero. Fixes: 2377c92e37fe ("powerpc/kexec_file: fix FDT size estimation for kdump kernel") Cc: stable@vger.kernel.org # v5.12+ Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230130014707.541110-1-mpe@ellerman.id.au

Merge tag 'powerpc-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2022-12-19T13:13:33Z

Pull powerpc updates from Michael Ellerman: - Add powerpc qspinlock implementation optimised for large system scalability and paravirt. See the merge message for more details - Enable objtool to be built on powerpc to generate mcount locations - Use a temporary mm for code patching with the Radix MMU, so the writable mapping is restricted to the patching CPU - Add an option to build the 64-bit big-endian kernel with the ELFv2 ABI - Sanitise user registers on interrupt entry on 64-bit Book3S - Many other small features and fixes Thanks to Aboorva Devarajan, Angel Iglesias, Benjamin Gray, Bjorn Helgaas, Bo Liu, Chen Lifu, Christoph Hellwig, Christophe JAILLET, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Deming Wang, Disha Goel, Dmitry Torokhov, Finn Thain, Geert Uytterhoeven, Gustavo A. R. Silva, Haowen Bai, Joel Stanley, Jordan Niethe, Julia Lawall, Kajol Jain, Laurent Dufour, Li zeming, Miaoqian Lin, Michael Jeanson, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Miehlbradt, Nicholas Piggin, Pali Rohár, Randy Dunlap, Rohan McLure, Russell Currey, Sathvika Vasireddy, Shaomin Deng, Stephen Kitt, Stephen Rothwell, Thomas Weißschuh, Tiezhu Yang, Uwe Kleine-König, Xie Shaowen, Xiu Jianfeng, XueBing Chen, Yang Yingliang, Zhang Jiaming, ruanjinjie, Jessica Yu, and Wolfram Sang. * tag 'powerpc-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (181 commits) powerpc/code-patching: Fix oops with DEBUG_VM enabled powerpc/qspinlock: Fix 32-bit build powerpc/prom: Fix 32-bit build powerpc/rtas: mandate RTAS syscall filtering powerpc/rtas: define pr_fmt and convert printk call sites powerpc/rtas: clean up includes powerpc/rtas: clean up rtas_error_log_max initialization powerpc/pseries/eeh: use correct API for error log size powerpc/rtas: avoid scheduling in rtas_os_term() powerpc/rtas: avoid device tree lookups in rtas_os_term() powerpc/rtasd: use correct OF API for event scan rate powerpc/rtas: document rtas_call() powerpc/pseries: unregister VPA when hot unplugging a CPU powerpc/pseries: reset the RCU watchdogs after a LPM powerpc: Take in account addition CPU node when building kexec FDT powerpc: export the CPU node count powerpc/cpuidle: Set CPUIDLE_FLAG_POLLING for snooze state powerpc/dts/fsl: Fix pca954x i2c-mux node names cxl: Remove unnecessary cxl_pci_window_alignment() selftests/powerpc: Fix resource leaks ...

powerpc: Take in account addition CPU node when building kexec FDT

2022-12-07T09:19:04Z

On a system with a large number of CPUs, the creation of the FDT for a kexec kernel may fail because the allocated FDT is not large enough. When this happens, such a message is displayed on the console: Unable to add ibm,processor-vadd-size property: FDT_ERR_NOSPACE The property's name may change depending when the buffer overwrite is detected. Obviously the created FDT is missing information, and it is expected that system dump or kexec kernel failed to run properly. When the FDT is allocated, the size of the FDT the kernel received at boot time is used and an extra size can be applied. Currently, only memory added after boot time is taken in account, not the CPU nodes. The extra size should take in account these additional CPU nodes and compute the required extra space. To achieve that, the size of a CPU node, including its subnode is computed once and multiplied by the number of additional CPU nodes. The assumption is that the size of the CPU node is _same_ for all the node, the only variable part should be the name "PowerPC,POWERxx@##" where "##" may vary a little. Signed-off-by: Laurent Dufour [mpe: Don't shadow function name w/variable, minor coding style changes] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20221110180619.15796-3-ldufour@linux.ibm.com

kexec: replace crash_mem_range with range

2022-11-18T21:55:07Z

We already have struct range, so just use it. Link: https://lkml.kernel.org/r/20220929042936.22012-4-bhe@redhat.com Signed-off-by: Li Chen Signed-off-by: Baoquan He Acked-by: Baoquan He Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Chen Lifu Cc: "Eric W . Biederman" Cc: Jianglei Nie Cc: Petr Mladek Cc: Russell King Cc: ye xingchen Cc: Zeal Robot Signed-off-by: Andrew Morton

powerpc/kexec: Fix build failure from uninitialised variable

2022-08-10T05:55:20Z

clang 14 won't build because ret is uninitialised and can be returned if both prop and fdtprop are NULL. Drop the ret variable and return an error in that failure case. Fixes: b1fc44eaa9ba ("pseries/iommu/ddw: Fix kdump to work in absence of ibm,dma-window") Suggested-by: Christophe Leroy Signed-off-by: Russell Currey Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220810054331.373761-1-ruscur@russell.cc

powerpc/64e: Fix kexec build error

2022-08-03T06:32:18Z

When building ppc64_book3e_allmodconfig the build fails with: arch/powerpc/kexec/file_load_64.c:1063:14: error: implicit declaration of function ‘firmware_has_feature’ 1063 | if (!firmware_has_feature(FW_FEATURE_LPAR)) | ^~~~~~~~~~~~~~~~~~~~ Add a direct include of asm/firmware.h to fix the error. Fixes: b1fc44eaa9ba ("pseries/iommu/ddw: Fix kdump to work in absence of ibm,dma-window") Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220803063152.1249270-1-mpe@ellerman.id.au

pseries/iommu/ddw: Fix kdump to work in absence of ibm,dma-window

2022-07-28T06:22:13Z

The pseries platform uses 32bit default DMA window (always 4K pages) and optional 64bit DMA window available via DDW ("Dynamic DMA Windows"), 64K or 2M pages. For ages the default one was not removed and a huge window was created in addition. Things changed with SRIOV-enabled PowerVM which creates a default-and-bigger DMA window in 64bit space (still using 4K pages) for IOV VFs so certain OSes do not need to use the DDW API in order to utilize all available TCE budget. Linux on the other hand removes the default window and creates a bigger one (with more TCEs or/and a bigger page size - 64K/2M) in a bid to map the entire RAM, and if the new window size is smaller than that - it still uses this new bigger window. The result is that the default window is removed but the "ibm,dma-window" property is not. When kdump is invoked, the existing code tries reusing the existing 64bit DMA window which location and parameters are stored in the device tree but this fails as the new property does not make it to the kdump device tree blob. So the code falls back to the default window which does not exist anymore although the device tree says that it does. The result of that is that PCI devices become unusable and cannot be used for kdumping. This preserves the DMA64 and DIRECT64 properties in the device tree blob for the crash kernel. Since the crash kernel setup is done after device drivers are loaded and probed, the proper DMA config is stored at least for boot time devices. Because DDW window is optional and the code configures the default window first, the existing code creates an IOMMU table descriptor for the non-existing default DMA window. It is harmless for kdump as it does not touch the actual window (only reads what is mapped and marks those IO pages as used) but it is bad for kexec which clears it thinking it is a smaller default window rather than a bigger DDW window. This removes the "ibm,dma-window" property from the device tree after a bigger window is created and the crash kernel setup picks it up. Fixes: 381ceda88c4c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping") Signed-off-by: Alexey Kardashevskiy Acked-by: Hari Bathini Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220629060614.1680476-1-aik@ozlabs.ru

powerpc/kexec_file: Add of_node_put() before goto

2021-10-22T04:22:02Z

Fix following coccicheck warning: ./arch/powerpc/kexec/file_load_64.c:698:1-22: WARNING: Function for_each_node_by_type should have of_node_put() before goto Early exits from for_each_node_by_type should decrement the node reference counter. Signed-off-by: Wan Jiabing Acked-by: Hari Bathini Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211018015418.10182-1-wanjiabing@vivo.com