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2024-10-31powerpc/ftrace: Add support for DYNAMIC_FTRACE_WITH_DIRECT_CALLSNaveen N Rao
Add support for DYNAMIC_FTRACE_WITH_DIRECT_CALLS similar to the arm64 implementation. ftrace direct calls allow custom trampolines to be called into directly from function ftrace call sites, bypassing the ftrace trampoline completely. This functionality is currently utilized by BPF trampolines to hook into kernel function entries. Since we have limited relative branch range, we support ftrace direct calls through support for DYNAMIC_FTRACE_WITH_CALL_OPS. In this approach, ftrace trampoline is not entirely bypassed. Rather, it is re-purposed into a stub that reads direct_call field from the associated ftrace_ops structure and branches into that, if it is not NULL. For this, it is sufficient if we can ensure that the ftrace trampoline is reachable from all traceable functions. When multiple ftrace_ops are associated with a call site, we utilize a call back to set pt_regs->orig_gpr3 that can then be tested on the return path from the ftrace trampoline to branch into the direct caller. Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241030070850.1361304-16-hbathini@linux.ibm.com
2024-10-31powerpc/ftrace: Add support for DYNAMIC_FTRACE_WITH_CALL_OPSNaveen N Rao
Implement support for DYNAMIC_FTRACE_WITH_CALL_OPS similar to the arm64 implementation. This works by patching-in a pointer to an associated ftrace_ops structure before each traceable function. If multiple ftrace_ops are associated with a call site, then a special ftrace_list_ops is used to enable iterating over all the registered ftrace_ops. If no ftrace_ops are associated with a call site, then a special ftrace_nop_ops structure is used to render the ftrace call as a no-op. ftrace trampoline can then read the associated ftrace_ops for a call site by loading from an offset from the LR, and branch directly to the associated function. The primary advantage with this approach is that we don't have to iterate over all the registered ftrace_ops for call sites that have a single ftrace_ops registered. This is the equivalent of implementing support for dynamic ftrace trampolines, which set up a special ftrace trampoline for each registered ftrace_ops and have individual call sites branch into those directly. A secondary advantage is that this gives us a way to add support for direct ftrace callers without having to resort to using stubs. The address of the direct call trampoline can be loaded from the ftrace_ops structure. To support this, we reserve a nop before each function on 32-bit powerpc. For 64-bit powerpc, two nops are reserved before each out-of-line stub. During ftrace activation, we update this location with the associated ftrace_ops pointer. Then, on ftrace entry, we load from this location and call into ftrace_ops->func(). For 64-bit powerpc, we ensure that the out-of-line stub area is doubleword aligned so that ftrace_ops address can be updated atomically. Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241030070850.1361304-15-hbathini@linux.ibm.com
2024-10-31powerpc64/ftrace: Support .text larger than 32MB with out-of-line stubsNaveen N Rao
We are restricted to a .text size of ~32MB when using out-of-line function profile sequence. Allow this to be extended up to the previous limit of ~64MB by reserving space in the middle of .text. A new config option CONFIG_PPC_FTRACE_OUT_OF_LINE_NUM_RESERVE is introduced to specify the number of function stubs that are reserved in .text. On boot, ftrace utilizes stubs from this area first before using the stub area at the end of .text. A ppc64le defconfig has ~44k functions that can be traced. A more conservative value of 32k functions is chosen as the default value of PPC_FTRACE_OUT_OF_LINE_NUM_RESERVE so that we do not allot more space than necessary by default. If building a kernel that only has 32k trace-able functions, we won't allot any more space at the end of .text during the pass on vmlinux.o. Otherwise, only the remaining functions get space for stubs at the end of .text. This default value should help cover a .text size of ~48MB in total (including space reserved at the end of .text which can cover up to 32MB), which should be sufficient for most common builds. For a very small kernel build, this can be set to 0. Or, this can be bumped up to a larger value to support vmlinux .text size up to ~64MB. Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241030070850.1361304-14-hbathini@linux.ibm.com
2024-10-31powerpc64/ftrace: Move ftrace sequence out of lineNaveen N Rao
Function profile sequence on powerpc includes two instructions at the beginning of each function: mflr r0 bl ftrace_caller The call to ftrace_caller() gets nop'ed out during kernel boot and is patched in when ftrace is enabled. Given the sequence, we cannot return from ftrace_caller with 'blr' as we need to keep LR and r0 intact. This results in link stack (return address predictor) imbalance when ftrace is enabled. To address that, we would like to use a three instruction sequence: mflr r0 bl ftrace_caller mtlr r0 Further more, to support DYNAMIC_FTRACE_WITH_CALL_OPS, we need to reserve two instruction slots before the function. This results in a total of five instruction slots to be reserved for ftrace use on each function that is traced. Move the function profile sequence out-of-line to minimize its impact. To do this, we reserve a single nop at function entry using -fpatchable-function-entry=1 and add a pass on vmlinux.o to determine the total number of functions that can be traced. This is then used to generate a .S file reserving the appropriate amount of space for use as ftrace stubs, which is built and linked into vmlinux. On bootup, the stub space is split into separate stubs per function and populated with the proper instruction sequence. A pointer to the associated stub is maintained in dyn_arch_ftrace. For modules, space for ftrace stubs is reserved from the generic module stub space. This is restricted to and enabled by default only on 64-bit powerpc, though there are some changes to accommodate 32-bit powerpc. This is done so that 32-bit powerpc could choose to opt into this based on further tests and benchmarks. As an example, after this patch, kernel functions will have a single nop at function entry: <kernel_clone>: addis r2,r12,467 addi r2,r2,-16028 nop mfocrf r11,8 ... When ftrace is enabled, the nop is converted to an unconditional branch to the stub associated with that function: <kernel_clone>: addis r2,r12,467 addi r2,r2,-16028 b ftrace_ool_stub_text_end+0x11b28 mfocrf r11,8 ... The associated stub: <ftrace_ool_stub_text_end+0x11b28>: mflr r0 bl ftrace_caller mtlr r0 b kernel_clone+0xc ... This change showed an improvement of ~10% in null_syscall benchmark on a Power 10 system with ftrace enabled. Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241030070850.1361304-13-hbathini@linux.ibm.com
2024-10-31powerpc/ftrace: Remove pointer to struct module from dyn_arch_ftraceNaveen N Rao
Pointer to struct module is only relevant for ftrace records belonging to kernel modules. Having this field in dyn_arch_ftrace wastes memory for all ftrace records belonging to the kernel. Remove the same in favour of looking up the module from the ftrace record address, similar to other architectures. Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241030070850.1361304-7-hbathini@linux.ibm.com
2024-10-29powerpc/64: Remove maple platformMichael Ellerman
The maple platform was added in 2004 [1], to support the "Maple" 970FX evaluation board. It was later used for IBM JS20/JS21 machines, as well as the Bimini machine, aka "Yellow Dog Powerstation". Sadly all those machines have passed into memory, and there's been no evidence for years that anyone is still using any of them. Remove the platform and related code. It can always be reinstated if there's interest. Note that this has no impact on support for 970FX based Power Macs. [1]: https://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux-fullhistory.git/commit/?id=f0d068d65c5e555ffcfbc189de32598f6f00770c Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241013102957.548291-1-mpe@ellerman.id.au
2024-10-29powerpc/pseries: Fix dtl_access_lock to be a rw_semaphoreMichael Ellerman
The dtl_access_lock needs to be a rw_sempahore, a sleeping lock, because the code calls kmalloc() while holding it, which can sleep: # echo 1 > /proc/powerpc/vcpudispatch_stats BUG: sleeping function called from invalid context at include/linux/sched/mm.h:337 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 199, name: sh preempt_count: 1, expected: 0 3 locks held by sh/199: #0: c00000000a0743f8 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x324/0x438 #1: c0000000028c7058 (dtl_enable_mutex){+.+.}-{3:3}, at: vcpudispatch_stats_write+0xd4/0x5f4 #2: c0000000028c70b8 (dtl_access_lock){+.+.}-{2:2}, at: vcpudispatch_stats_write+0x220/0x5f4 CPU: 0 PID: 199 Comm: sh Not tainted 6.10.0-rc4 #152 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries Call Trace: dump_stack_lvl+0x130/0x148 (unreliable) __might_resched+0x174/0x410 kmem_cache_alloc_noprof+0x340/0x3d0 alloc_dtl_buffers+0x124/0x1ac vcpudispatch_stats_write+0x2a8/0x5f4 proc_reg_write+0xf4/0x150 vfs_write+0xfc/0x438 ksys_write+0x88/0x148 system_call_exception+0x1c4/0x5a0 system_call_common+0xf4/0x258 Fixes: 06220d78f24a ("powerpc/pseries: Introduce rwlock to gatekeep DTLB usage") Tested-by: Kajol Jain <kjain@linux.ibm.com> Reviewed-by: Nysal Jan K.A <nysal@linux.ibm.com> Reviewed-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20240819122401.513203-1-mpe@ellerman.id.au
2024-10-29powerpc/machdep: Drop include of dma-mapping.hMichael Ellerman
Drop the include of dma-mapping.h in machdep.h, replace it with forward declarations of struct device and struct pci_dev, and include time64.h and page.h which are required for time64_t and pgprot_t respectively. Add direct includes of some other headers to some files that were getting them via machdep.h. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241009051826.132805-2-mpe@ellerman.id.au
2024-10-29powerpc/machdep: Drop include of seq_file.hMichael Ellerman
Drop the include of seq_file.h in machdep.h, replace it with a forward declaration of struct seq_file, which is all that's required. Add direct includes of seq_file.h to some files that were getting seq_file.h via machdep.h. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241009051826.132805-1-mpe@ellerman.id.au
2024-10-28asm-generic: provide generic page_to_phys and phys_to_page implementationsChristoph Hellwig
page_to_phys is duplicated by all architectures, and from some strange reason placed in <asm/io.h> where it doesn't fit at all. phys_to_page is only provided by a few architectures despite having a lot of open coded users. Provide generic versions in <asm-generic/memory_model.h> to make these helpers more easily usable. Note with this patch powerpc loses the CONFIG_DEBUG_VIRTUAL pfn_valid check. It will be added back in a generic version later. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2024-10-25KVM: PPC: Use kvm_faultin_pfn() to handle page faults on Book3s PRSean Christopherson
Convert Book3S PR to __kvm_faultin_pfn()+kvm_release_faultin_page(), which are new APIs to consolidate arch code and provide consistent behavior across all KVM architectures. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20241010182427.1434605-65-seanjc@google.com>
2024-10-25KVM: PPC: Drop unused @kvm_ro param from kvmppc_book3s_instantiate_page()Sean Christopherson
Drop @kvm_ro from kvmppc_book3s_instantiate_page() as it is now only written, and never read. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20241010182427.1434605-63-seanjc@google.com>
2024-10-23book3s64/radix: Refactoring common kfence related functionsRitesh Harjani (IBM)
Both radix and hash on book3s requires to detect if kfence early init is enabled or not. Hash needs to disable kfence if early init is not enabled because with kfence the linear map is mapped using PAGE_SIZE rather than 16M mapping. We don't support multiple page sizes for slb entry used for kernel linear map in book3s64. This patch refactors out the common functions required to detect kfence early init is enabled or not. Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/f4a787224fbe5bb787158ace579780c0257f6602.1729271995.git.ritesh.list@gmail.com
2024-10-23book3s64/hash: Add kfence functionalityRitesh Harjani (IBM)
Now that linear map functionality of debug_pagealloc is made generic, enable kfence to use this generic infrastructure. 1. Define kfence related linear map variables. - u8 *linear_map_kf_hash_slots; - unsigned long linear_map_kf_hash_count; - DEFINE_RAW_SPINLOCK(linear_map_kf_hash_lock); 2. The linear map size allocated in RMA region is quite small (KFENCE_POOL_SIZE >> PAGE_SHIFT) which is 512 bytes by default. 3. kfence pool memory is reserved using memblock_phys_alloc() which has can come from anywhere. (default 255 objects => ((1+255) * 2) << PAGE_SHIFT = 32MB) 4. The hash slot information for kfence memory gets added in linear map in hash_linear_map_add_slot() (which also adds for debug_pagealloc). Reported-by: Pavithra Prakash <pavrampu@linux.vnet.ibm.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/5c2b61941b344077a2b8654dab46efa0322af3af.1729271995.git.ritesh.list@gmail.com
2024-10-23book3s64/hash: Remove kfence support temporarilyRitesh Harjani (IBM)
Kfence on book3s Hash on pseries is anyways broken. It fails to boot due to RMA size limitation. That is because, kfence with Hash uses debug_pagealloc infrastructure. debug_pagealloc allocates linear map for entire dram size instead of just kfence relevant objects. This means for 16TB of DRAM it will require (16TB >> PAGE_SHIFT) which is 256MB which is half of RMA region on P8. crash kernel reserves 256MB and we also need 2048 * 16KB * 3 for emergency stack and some more for paca allocations. That means there is not enough memory for reserving the full linear map in the RMA region, if the DRAM size is too big (>=16TB) (The issue is seen above 8TB with crash kernel 256 MB reservation). Now Kfence does not require linear memory map for entire DRAM. It only needs for kfence objects. So this patch temporarily removes the kfence functionality since debug_pagealloc code needs some refactoring. We will bring in kfence on Hash support in later patches. Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/1761bc39674473c8878dedca15e0d9a0d3a1b528.1729271995.git.ritesh.list@gmail.com
2024-10-21powerpc/fadump: Move fadump_cma_init to setup_arch() after initmem_init()Ritesh Harjani (IBM)
During early init CMA_MIN_ALIGNMENT_BYTES can be PAGE_SIZE, since pageblock_order is still zero and it gets initialized later during initmem_init() e.g. setup_arch() -> initmem_init() -> sparse_init() -> set_pageblock_order() One such use case where this causes issue is - early_setup() -> early_init_devtree() -> fadump_reserve_mem() -> fadump_cma_init() This causes CMA memory alignment check to be bypassed in cma_init_reserved_mem(). Then later cma_activate_area() can hit a VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) if the reserved memory area was not pageblock_order aligned. Fix it by moving the fadump_cma_init() after initmem_init(), where other such cma reservations also gets called. <stack trace> ============== page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10010 flags: 0x13ffff800000000(node=1|zone=0|lastcpupid=0x7ffff) CMA raw: 013ffff800000000 5deadbeef0000100 5deadbeef0000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) ------------[ cut here ]------------ kernel BUG at mm/page_alloc.c:778! Call Trace: __free_one_page+0x57c/0x7b0 (unreliable) free_pcppages_bulk+0x1a8/0x2c8 free_unref_page_commit+0x3d4/0x4e4 free_unref_page+0x458/0x6d0 init_cma_reserved_pageblock+0x114/0x198 cma_init_reserved_areas+0x270/0x3e0 do_one_initcall+0x80/0x2f8 kernel_init_freeable+0x33c/0x530 kernel_init+0x34/0x26c ret_from_kernel_user_thread+0x14/0x1c Fixes: 11ac3e87ce09 ("mm: cma: use pageblock_order as the single alignment") Suggested-by: David Hildenbrand <david@redhat.com> Reported-by: Sachin P Bappalige <sachinpb@linux.ibm.com> Acked-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/3ae208e48c0d9cefe53d2dc4f593388067405b7d.1729146153.git.ritesh.list@gmail.com
2024-10-16powerpc/vdso: Flag VDSO64 entry points as functionsChristophe Leroy
On powerpc64 as shown below by readelf, vDSO functions symbols have type NOTYPE. $ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg ELF Header: Magic: 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 Class: ELF64 Data: 2's complement, big endian Version: 1 (current) OS/ABI: UNIX - System V ABI Version: 0 Type: DYN (Shared object file) Machine: PowerPC64 Version: 0x1 ... Symbol table '.dynsym' contains 12 entries: Num: Value Size Type Bind Vis Ndx Name ... 1: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 ... 4: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15 5: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 Symbol table '.symtab' contains 56 entries: Num: Value Size Type Bind Vis Ndx Name ... 45: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15 46: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __kernel_getcpu 47: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __kernel_clock_getres To overcome that, commit ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64") was applied to have selftests also look for NOTYPE symbols, but the correct fix should be to flag VDSO entry points as functions. The original commit that brought VDSO support into powerpc/64 has the following explanation: Note that the symbols exposed by the vDSO aren't "normal" function symbols, apps can't be expected to link against them directly, the vDSO's are both seen as if they were linked at 0 and the symbols just contain offsets to the various functions. This is done on purpose to avoid a relocation step (ppc64 functions normally have descriptors with abs addresses in them). When glibc uses those functions, it's expected to use it's own trampolines that know how to reach them. The descriptors it's talking about are the OPD function descriptors used on ABI v1 (big endian). But it would be more correct for a text symbol to have type function, even if there's no function descriptor for it. glibc has a special case already for handling the VDSO symbols which creates a fake opd pointing at the kernel symbol. So changing the VDSO symbol type to function shouldn't affect that. For ABI v2, there is no function descriptors and VDSO functions can safely have function type. So lets flag VDSO entry points as functions and revert the selftest change. Link: https://github.com/mpe/linux-fullhistory/commit/5f2dd691b62da9d9cc54b938f8b29c22c93cb805 Fixes: ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-By: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/b6ad2f1ee9887af3ca5ecade2a56f4acda517a85.1728512263.git.christophe.leroy@csgroup.eu
2024-10-16powerpc/vdso: Implement __arch_get_vdso_rng_data()Christophe Leroy
VDSO time functions do not call any other function, so they don't need to save/restore LR. However, retrieving the address of VDSO data page requires using LR hence saving then restoring it, which can be heavy on some CPUs. On the other hand, VDSO functions on powerpc are not standard functions and require a wrapper function to call C VDSO functions. And that wrapper has to save and restore LR in order to call the C VDSO function, so retrieving VDSO data page address in that wrapper doesn't require additional save/restore of LR. For random VDSO functions it is a bit different. Because the function calls __arch_chacha20_blocks_nostack(), it saves and restores LR. Retrieving VDSO data page address can then be done there without additional save/restore of LR. So lets implement __arch_get_vdso_rng_data() and simplify the wrapper. It starts paving the way for the day powerpc will implement a more standard ABI for VDSO functions. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/a1a9bd0df508f1b5c04684b7366940577dfc6262.1727858295.git.christophe.leroy@csgroup.eu
2024-10-16powerpc/vdso: Add a page for non-time dataChristophe Leroy
The page containing VDSO time data is swapped with the one containing TIME namespace data when a process uses a non-root time namespace. For other data like powerpc specific data and RNG data, it means tracking whether time namespace is the root one or not to know which page to use. Simplify the logic behind by moving time data out of first data page so that the first data page which contains everything else always remains the first page. Time data is in the second or third page depending on selected time namespace. While we are playing with get_datapage macro, directly take into account the data offset inside the macro instead of adding that offset afterwards. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/0557d3ec898c1d0ea2fc59fa8757618e524c5d94.1727858295.git.christophe.leroy@csgroup.eu
2024-10-16vdso: Introduce vdso/page.hVincenzo Frascino
The VDSO implementation includes headers from outside of the vdso/ namespace. Introduce vdso/page.h to make sure that the generic library uses only the allowed namespace. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k Link: https://lore.kernel.org/all/20241014151340.1639555-3-vincenzo.frascino@arm.com
2024-10-15powerpc/vdso: Remove timekeeper includesThomas Weißschuh
Since the generic VDSO clock mode storage is used, this header file is unused and can be removed. This avoids including a non-VDSO header while building the VDSO, which can lead to compilation errors. Also drop the comment which is out of date and in the wrong place. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20241010-vdso-generic-arch_update_vsyscall-v1-4-7fe5a3ea4382@linutronix.de
2024-10-15ftrace: Consolidate ftrace_regs accessor functions for archs using pt_regsSteven Rostedt
Most architectures use pt_regs within ftrace_regs making a lot of the accessor functions just calls to the pt_regs internally. Instead of duplication this effort, use a HAVE_ARCH_FTRACE_REGS for architectures that have their own ftrace_regs that is not based on pt_regs and will define all the accessor functions, and for the architectures that just use pt_regs, it will leave it undefined, and the default accessor functions will be used. Note, this will also make it easier to add new accessor functions to ftrace_regs as it will mean having to touch less architectures. Cc: <linux-arch@vger.kernel.org> Cc: "x86@kernel.org" <x86@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Naveen N Rao <naveen@kernel.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/20241010202114.2289f6fd@gandalf.local.home Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390 Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> # powerpc Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-10-10ftrace: Make ftrace_regs abstract from direct useSteven Rostedt
ftrace_regs was created to hold registers that store information to save function parameters, return value and stack. Since it is a subset of pt_regs, it should only be used by its accessor functions. But because pt_regs can easily be taken from ftrace_regs (on most archs), it is tempting to use it directly. But when running on other architectures, it may fail to build or worse, build but crash the kernel! Instead, make struct ftrace_regs an empty structure and have the architectures define __arch_ftrace_regs and all the accessor functions will typecast to it to get to the actual fields. This will help avoid usage of ftrace_regs directly. Link: https://lore.kernel.org/all/20241007171027.629bdafd@gandalf.local.home/ Cc: "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org> Cc: "x86@kernel.org" <x86@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Naveen N Rao <naveen@kernel.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/20241008230628.958778821@goodmis.org Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390 Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-09-21Merge tag 'mm-stable-2024-09-20-02-31' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Along with the usual shower of singleton patches, notable patch series in this pull request are: - "Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds consistency to the APIs and behaviour of these two core allocation functions. This also simplifies/enables Rustification. - "Some cleanups for shmem" from Baolin Wang. No functional changes - mode code reuse, better function naming, logic simplifications. - "mm: some small page fault cleanups" from Josef Bacik. No functional changes - code cleanups only. - "Various memory tiering fixes" from Zi Yan. A small fix and a little cleanup. - "mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and simplifications and .text shrinkage. - "Kernel stack usage histogram" from Pasha Tatashin and Shakeel Butt. This is a feature, it adds new feilds to /proc/vmstat such as $ grep kstack /proc/vmstat kstack_1k 3 kstack_2k 188 kstack_4k 11391 kstack_8k 243 kstack_16k 0 which tells us that 11391 processes used 4k of stack while none at all used 16k. Useful for some system tuning things, but partivularly useful for "the dynamic kernel stack project". - "kmemleak: support for percpu memory leak detect" from Pavel Tikhomirov. Teaches kmemleak to detect leaksage of percpu memory. - "mm: memcg: page counters optimizations" from Roman Gushchin. "3 independent small optimizations of page counters". - "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from David Hildenbrand. Improves PTE/PMD splitlock detection, makes powerpc/8xx work correctly by design rather than by accident. - "mm: remove arch_make_page_accessible()" from David Hildenbrand. Some folio conversions which make arch_make_page_accessible() unneeded. - "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David Finkel. Cleans up and fixes our handling of the resetting of the cgroup/process peak-memory-use detector. - "Make core VMA operations internal and testable" from Lorenzo Stoakes. Rationalizaion and encapsulation of the VMA manipulation APIs. With a view to better enable testing of the VMA functions, even from a userspace-only harness. - "mm: zswap: fixes for global shrinker" from Takero Funaki. Fix issues in the zswap global shrinker, resulting in improved performance. - "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill in some missing info in /proc/zoneinfo. - "mm: replace follow_page() by folio_walk" from David Hildenbrand. Code cleanups and rationalizations (conversion to folio_walk()) resulting in the removal of follow_page(). - "improving dynamic zswap shrinker protection scheme" from Nhat Pham. Some tuning to improve zswap's dynamic shrinker. Significant reductions in swapin and improvements in performance are shown. - "mm: Fix several issues with unaccepted memory" from Kirill Shutemov. Improvements to the new unaccepted memory feature, - "mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on DAX PUDs. This was missing, although nobody seems to have notied yet. - "Introduce a store type enum for the Maple tree" from Sidhartha Kumar. Cleanups and modest performance improvements for the maple tree library code. - "memcg: further decouple v1 code from v2" from Shakeel Butt. Move more cgroup v1 remnants away from the v2 memcg code. - "memcg: initiate deprecation of v1 features" from Shakeel Butt. Adds various warnings telling users that memcg v1 features are deprecated. - "mm: swap: mTHP swap allocator base on swap cluster order" from Chris Li. Greatly improves the success rate of the mTHP swap allocation. - "mm: introduce numa_memblks" from Mike Rapoport. Moves various disparate per-arch implementations of numa_memblk code into generic code. - "mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly improves the performance of munmap() of swap-filled ptes. - "support large folio swap-out and swap-in for shmem" from Baolin Wang. With this series we no longer split shmem large folios into simgle-page folios when swapping out shmem. - "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice performance improvements and code reductions for gigantic folios. - "support shmem mTHP collapse" from Baolin Wang. Adds support for khugepaged's collapsing of shmem mTHP folios. - "mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect() performance regression due to the addition of mseal(). - "Increase the number of bits available in page_type" from Matthew Wilcox. Increases the number of bits available in page_type! - "Simplify the page flags a little" from Matthew Wilcox. Many legacy page flags are now folio flags, so the page-based flags and their accessors/mutators can be removed. - "mm: store zero pages to be swapped out in a bitmap" from Usama Arif. An optimization which permits us to avoid writing/reading zero-filled zswap pages to backing store. - "Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race window which occurs when a MAP_FIXED operqtion is occurring during an unrelated vma tree walk. - "mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of the vma_merge() functionality, making ot cleaner, more testable and better tested. - "misc fixups for DAMON {self,kunit} tests" from SeongJae Park. Minor fixups of DAMON selftests and kunit tests. - "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang. Code cleanups and folio conversions. - "Shmem mTHP controls and stats improvements" from Ryan Roberts. Cleanups for shmem controls and stats. - "mm: count the number of anonymous THPs per size" from Barry Song. Expose additional anon THP stats to userspace for improved tuning. - "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more folio conversions and removal of now-unused page-based APIs. - "replace per-quota region priorities histogram buffer with per-context one" from SeongJae Park. DAMON histogram rationalization. - "Docs/damon: update GitHub repo URLs and maintainer-profile" from SeongJae Park. DAMON documentation updates. - "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and improve related doc and warn" from Jason Wang: fixes usage of page allocator __GFP_NOFAIL and GFP_ATOMIC flags. - "mm: split underused THPs" from Yu Zhao. Improve THP=always policy. This was overprovisioning THPs in sparsely accessed memory areas. - "zram: introduce custom comp backends API" frm Sergey Senozhatsky. Add support for zram run-time compression algorithm tuning. - "mm: Care about shadow stack guard gap when getting an unmapped area" from Mark Brown. Fix up the various arch_get_unmapped_area() implementations to better respect guard areas. - "Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability of mem_cgroup_iter() and various code cleanups. - "mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge pfnmap support. - "resource: Fix region_intersects() vs add_memory_driver_managed()" from Huang Ying. Fix a bug in region_intersects() for systems with CXL memory. - "mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches a couple more code paths to correctly recover from the encountering of poisoned memry. - "mm: enable large folios swap-in support" from Barry Song. Support the swapin of mTHP memory into appropriately-sized folios, rather than into single-page folios" * tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (416 commits) zram: free secondary algorithms names uprobes: turn xol_area->pages[2] into xol_area->page uprobes: introduce the global struct vm_special_mapping xol_mapping Revert "uprobes: use vm_special_mapping close() functionality" mm: support large folios swap-in for sync io devices mm: add nr argument in mem_cgroup_swapin_uncharge_swap() helper to support large folios mm: fix swap_read_folio_zeromap() for large folios with partial zeromap mm/debug_vm_pgtable: Use pxdp_get() for accessing page table entries set_memory: add __must_check to generic stubs mm/vma: return the exact errno in vms_gather_munmap_vmas() memcg: cleanup with !CONFIG_MEMCG_V1 mm/show_mem.c: report alloc tags in human readable units mm: support poison recovery from copy_present_page() mm: support poison recovery from do_cow_fault() resource, kunit: add test case for region_intersects() resource: make alloc_free_mem_region() works for iomem_resource mm: z3fold: deprecate CONFIG_Z3FOLD vfio/pci: implement huge_fault support mm/arm64: support large pfn mappings mm/x86: support large pfn mappings ...
2024-09-19Merge tag 'powerpc-6.12-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Reduce alignment constraints on STRICT_KERNEL_RWX and speed-up TLB misses on 8xx and 603 - Replace kretprobe code with rethook and enable fprobe - Remove the "fast endian switch" syscall - Handle DLPAR device tree updates in kernel, allowing the deprecation of the binary /proc/powerpc/ofdt interface Thanks to Abhishek Dubey, Alex Shi, Benjamin Gray, Christophe Leroy, Gaosheng Cui, Gautam Menghani, Geert Uytterhoeven, Haren Myneni, Hari Bathini, Huang Xiaojia, Jinjie Ruan, Madhavan Srinivasan, Miguel Ojeda, Mina Almasry, Narayana Murty N, Naveen Rao, Rob Herring (Arm), Scott Cheloha, Segher Boessenkool, Stephen Rothwell, Thomas Zimmermann, Uwe Kleine-König, Vaibhav Jain, and Zhang Zekun. * tag 'powerpc-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (59 commits) powerpc/atomic: Use YZ constraints for DS-form instructions MAINTAINERS: powerpc: Add Maddy powerpc: Switch back to struct platform_driver::remove() powerpc/pseries/eeh: Fix pseries_eeh_err_inject selftests/powerpc: Allow building without static libc macintosh/via-pmu: register_pmu_pm_ops() can be __init powerpc: Stop using no_llseek powerpc/64s: Remove the "fast endian switch" syscall powerpc/mm/64s: Restrict THP to Radix or HPT w/64K pages powerpc/mm/64s: Move THP reqs into a separate symbol powerpc/64s: Make mmu_hash_ops __ro_after_init powerpc: Replace kretprobe code with rethook on powerpc powerpc: pseries: Constify struct kobj_type powerpc: powernv: Constify struct kobj_type powerpc: Constify struct kobj_type powerpc/pseries/dlpar: Add device tree nodes for DLPAR IO add powerpc/pseries/dlpar: Remove device tree node for DLPAR IO remove powerpc/pseries: Use correct data types from pseries_hp_errorlog struct powerpc/vdso: Inconditionally use CFUNC macro powerpc/32: Implement validation of emergency stack ...
2024-09-18Merge tag 'random-6.12-rc1-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/crng/random Pull random number generator updates from Jason Donenfeld: "Originally I'd planned on sending each of the vDSO getrandom() architecture ports to their respective arch trees. But as we started to work on this, we found lots of interesting issues in the shared code and infrastructure, the fixes for which the various archs needed to base their work. So in the end, this turned into a nice collaborative effort fixing up issues and porting to 5 new architectures -- arm64, powerpc64, powerpc32, s390x, and loongarch64 -- with everybody pitching in and commenting on each other's code. It was a fun development cycle. This contains: - Numerous fixups to the vDSO selftest infrastructure, getting it running successfully on more platforms, and fixing bugs in it. - Additions to the vDSO getrandom & chacha selftests. Basically every time manual review unearthed a bug in a revision of an arch patch, or an ambiguity, the tests were augmented. By the time the last arch was submitted for review, s390x, v1 of the series was essentially fine right out of the gate. - Fixes to the the generic C implementation of vDSO getrandom, to build and run successfully on all archs, decoupling it from assumptions we had (unintentionally) made on x86_64 that didn't carry through to the other architectures. - Port of vDSO getrandom to LoongArch64, from Xi Ruoyao and acked by Huacai Chen. - Port of vDSO getrandom to ARM64, from Adhemerval Zanella and acked by Will Deacon. - Port of vDSO getrandom to PowerPC, in both 32-bit and 64-bit varieties, from Christophe Leroy and acked by Michael Ellerman. - Port of vDSO getrandom to S390X from Heiko Carstens, the arch maintainer. While it'd be natural for there to be things to fix up over the course of the development cycle, these patches got a decent amount of review from a fairly diverse crew of folks on the mailing lists, and, for the most part, they've been cooking in linux-next, which has been helpful for ironing out build issues. In terms of architectures, I think that mostly takes care of the important 64-bit archs with hardware still being produced and running production loads in settings where vDSO getrandom is likely to help. Arguably there's still RISC-V left, and we'll see for 6.13 whether they find it useful and submit a port" * tag 'random-6.12-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (47 commits) selftests: vDSO: check cpu caps before running chacha test s390/vdso: Wire up getrandom() vdso implementation s390/vdso: Move vdso symbol handling to separate header file s390/vdso: Allow alternatives in vdso code s390/module: Provide find_section() helper s390/facility: Let test_facility() generate static branch if possible s390/alternatives: Remove ALT_FACILITY_EARLY s390/facility: Disable compile time optimization for decompressor code selftests: vDSO: fix vdso_config for s390 selftests: vDSO: fix ELF hash table entry size for s390x powerpc/vdso: Wire up getrandom() vDSO implementation on VDSO64 powerpc/vdso: Wire up getrandom() vDSO implementation on VDSO32 powerpc/vdso: Refactor CFLAGS for CVDSO build powerpc/vdso32: Add crtsavres mm: Define VM_DROPPABLE for powerpc/32 powerpc/vdso: Fix VDSO data access when running in a non-root time namespace selftests: vDSO: don't include generated headers for chacha test arm64: vDSO: Wire up getrandom() vDSO implementation arm64: alternative: make alternative_has_cap_likely() VDSO compatible selftests: vDSO: also test counter in vdso_test_chacha ...
2024-09-18Merge tag 'rcu.release.v6.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux Pull RCU updates from Neeraj Upadhyay: "Context tracking: - rename context tracking state related symbols and remove references to "dynticks" in various context tracking state variables and related helpers - force context_tracking_enabled_this_cpu() to be inlined to avoid leaving a noinstr section CSD lock: - enhance CSD-lock diagnostic reports - add an API to provide an indication of ongoing CSD-lock stall nocb: - update and simplify RCU nocb code to handle (de-)offloading of callbacks only for offline CPUs - fix RT throttling hrtimer being armed from offline CPU rcutorture: - remove redundant rcu_torture_ops get_gp_completed fields - add SRCU ->same_gp_state and ->get_comp_state functions - add generic test for NUM_ACTIVE_*RCU_POLL* for testing RCU and SRCU polled grace periods - add CFcommon.arch for arch-specific Kconfig options - print number of update types in rcu_torture_write_types() - add rcutree.nohz_full_patience_delay testing to the TREE07 scenario - add a stall_cpu_repeat module parameter to test repeated CPU stalls - add argument to limit number of CPUs a guest OS can use in torture.sh rcustall: - abbreviate RCU CPU stall warnings during CSD-lock stalls - Allow dump_cpu_task() to be called without disabling preemption - defer printing stall-warning backtrace when holding rcu_node lock srcu: - make SRCU gp seq wrap-around faster - add KCSAN checks for concurrent updates to ->srcu_n_exp_nodelay and ->reschedule_count which are used in heuristics governing auto-expediting of normal SRCU grace periods and grace-period-state-machine delays - mark idle SRCU-barrier callbacks to help identify stuck SRCU-barrier callback rcu tasks: - remove RCU Tasks Rude asynchronous APIs as they are no longer used - stop testing RCU Tasks Rude asynchronous APIs - fix access to non-existent percpu regions - check processor-ID assumptions during chosen CPU calculation for callback enqueuing - update description of rtp->tasks_gp_seq grace-period sequence number - add rcu_barrier_cb_is_done() to identify whether a given rcu_barrier callback is stuck - mark idle Tasks-RCU-barrier callbacks - add *torture_stats_print() functions to print detailed diagnostics for Tasks-RCU variants - capture start time of rcu_barrier_tasks*() operation to help distinguish a hung barrier operation from a long series of barrier operations refscale: - add a TINY scenario to support tests of Tiny RCU and Tiny SRCU - optimize process_durations() operation rcuscale: - dump stacks of stalled rcu_scale_writer() instances and grace-period statistics when rcu_scale_writer() stalls - mark idle RCU-barrier callbacks to identify stuck RCU-barrier callbacks - print detailed grace-period and barrier diagnostics on rcu_scale_writer() hangs for Tasks-RCU variants - warn if async module parameter is specified for RCU implementations that do not have async primitives such as RCU Tasks Rude - make all writer tasks report upon hang - tolerate repeated GFP_KERNEL failure in rcu_scale_writer() - use special allocator for rcu_scale_writer() - NULL out top-level pointers to heap memory to avoid double-free bugs on modprobe failures - maintain per-task instead of per-CPU callbacks count to avoid any issues with migration of either tasks or callbacks - constify struct ref_scale_ops Fixes: - use system_unbound_wq for kfree_rcu work to avoid disturbing isolated CPUs Misc: - warn on unexpected rcu_state.srs_done_tail state - better define "atomic" for list_replace_rcu() and hlist_replace_rcu() routines - annotate struct kvfree_rcu_bulk_data with __counted_by()" * tag 'rcu.release.v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (90 commits) rcu: Defer printing stall-warning backtrace when holding rcu_node lock rcu/nocb: Remove superfluous memory barrier after bypass enqueue rcu/nocb: Conditionally wake up rcuo if not already waiting on GP rcu/nocb: Fix RT throttling hrtimer armed from offline CPU rcu/nocb: Simplify (de-)offloading state machine context_tracking: Tag context_tracking_enabled_this_cpu() __always_inline context_tracking, rcu: Rename rcu_dyntick trace event into rcu_watching rcu: Update stray documentation references to rcu_dynticks_eqs_{enter, exit}() rcu: Rename rcu_momentary_dyntick_idle() into rcu_momentary_eqs() rcu: Rename rcu_implicit_dynticks_qs() into rcu_watching_snap_recheck() rcu: Rename dyntick_save_progress_counter() into rcu_watching_snap_save() rcu: Rename struct rcu_data .exp_dynticks_snap into .exp_watching_snap rcu: Rename struct rcu_data .dynticks_snap into .watching_snap rcu: Rename rcu_dynticks_zero_in_eqs() into rcu_watching_zero_in_eqs() rcu: Rename rcu_dynticks_in_eqs_since() into rcu_watching_snap_stopped_since() rcu: Rename rcu_dynticks_in_eqs() into rcu_watching_snap_in_eqs() rcu: Rename rcu_dynticks_eqs_online() into rcu_watching_online() context_tracking, rcu: Rename rcu_dynticks_curr_cpu_in_eqs() into rcu_is_watching_curr_cpu() context_tracking, rcu: Rename rcu_dynticks_task*() into rcu_task*() refscale: Constify struct ref_scale_ops ...
2024-09-17powerpc/atomic: Use YZ constraints for DS-form instructionsMichael Ellerman
The 'ld' and 'std' instructions require a 4-byte aligned displacement because they are DS-form instructions. But the "m" asm constraint doesn't enforce that. That can lead to build errors if the compiler chooses a non-aligned displacement, as seen with GCC 14: /tmp/ccuSzwiR.s: Assembler messages: /tmp/ccuSzwiR.s:2579: Error: operand out of domain (39 is not a multiple of 4) make[5]: *** [scripts/Makefile.build:229: net/core/page_pool.o] Error 1 Dumping the generated assembler shows: ld 8,39(8) # MEM[(const struct atomic64_t *)_29].counter, t Use the YZ constraints to tell the compiler either to generate a DS-form displacement, or use an X-form instruction, either of which prevents the build error. See commit 2d43cc701b96 ("powerpc/uaccess: Fix build errors seen with GCC 13/14") for more details on the constraint letters. Fixes: 9f0cbea0d8cc ("[POWERPC] Implement atomic{, 64}_{read, write}() without volatile") Cc: stable@vger.kernel.org # v2.6.24+ Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Closes: https://lore.kernel.org/all/20240913125302.0a06b4c7@canb.auug.org.au Tested-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240916120510.2017749-1-mpe@ellerman.id.au
2024-09-17mm: always define pxx_pgprot()Peter Xu
There're: - 8 archs (arc, arm64, include, mips, powerpc, s390, sh, x86) that support pte_pgprot(). - 2 archs (x86, sparc) that support pmd_pgprot(). - 1 arch (x86) that support pud_pgprot(). Always define them to be used in generic code, and then we don't need to fiddle with "#ifdef"s when doing so. Link: https://lkml.kernel.org/r/20240826204353.2228736-9-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Gavin Shan <gshan@redhat.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Niklas Schnelle <schnelle@linux.ibm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-13powerpc/vdso: Wire up getrandom() vDSO implementation on VDSO32Christophe Leroy
To be consistent with other VDSO functions, the function is called __kernel_getrandom() __arch_chacha20_blocks_nostack() fonction is implemented basically with 32 bits operations. It performs 4 QUARTERROUND operations in parallele. There are enough registers to avoid using the stack: On input: r3: output bytes r4: 32-byte key input r5: 8-byte counter input/output r6: number of 64-byte blocks to write to output During operation: stack: pointer to counter (r5) and non-volatile registers (r14-131) r0: counter of blocks (initialised with r6) r4: Value '4' after key has been read, used for indexing r5-r12: key r14-r15: block counter r16-r31: chacha state At the end: r0, r6-r12: Zeroised r5, r14-r31: Restored Performance on powerpc 885 (using kernel selftest): ~# ./vdso_test_getrandom bench-single vdso: 25000000 times in 62.938002291 seconds libc: 25000000 times in 535.581916866 seconds syscall: 25000000 times in 531.525042806 seconds Performance on powerpc 8321 (using kernel selftest): ~# ./vdso_test_getrandom bench-single vdso: 25000000 times in 16.899318858 seconds libc: 25000000 times in 131.050596522 seconds syscall: 25000000 times in 129.794790389 seconds This first patch adds support for VDSO32. As selftests cannot easily be generated only for VDSO32, and because the following patch brings support for VDSO64 anyway, this patch opts out all code in __arch_chacha20_blocks_nostack() so that vdso_test_chacha will not fail to compile and will not crash on PPC64/PPC64LE, allthough the selftest itself will fail. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2024-09-13powerpc/vdso: Fix VDSO data access when running in a non-root time namespaceChristophe Leroy
When running in a non-root time namespace, the global VDSO data page is replaced by a dedicated namespace data page and the global data page is mapped next to it. Detailed explanations can be found at commit 660fd04f9317 ("lib/vdso: Prepare for time namespace support"). When it happens, __kernel_get_syscall_map and __kernel_get_tbfreq and __kernel_sync_dicache don't work anymore because they read 0 instead of the data they need. To address that, clock_mode has to be read. When it is set to VDSO_CLOCKMODE_TIMENS, it means it is a dedicated namespace data page and the global data is located on the following page. Add a macro called get_realdatapage which reads clock_mode and add PAGE_SIZE to the pointer provided by get_datapage macro when clock_mode is equal to VDSO_CLOCKMODE_TIMENS. Use this new macro instead of get_datapage macro except for time functions as they handle it internally. Fixes: 74205b3fc2ef ("powerpc/vdso: Add support for time namespaces") Reported-by: Jason A. Donenfeld <Jason@zx2c4.com> Closes: https://lore.kernel.org/all/ZtnYqZI-nrsNslwy@zx2c4.com/ Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2024-09-10powerpc/pseries/eeh: Fix pseries_eeh_err_injectNarayana Murty N
VFIO_EEH_PE_INJECT_ERR ioctl is currently failing on pseries due to missing implementation of err_inject eeh_ops for pseries. This patch implements pseries_eeh_err_inject in eeh_ops/pseries eeh_ops. Implements support for injecting MMIO load/store error for testing from user space. The check on PCI error type (bus type) code is moved to platform code, since the eeh_pe_inject_err can be allowed to more error types depending on platform requirement. Removal of the check for 'type' in eeh_pe_inject_err() doesn't impact PowerNV as pnv_eeh_err_inject() already has an equivalent check in place. Signed-off-by: Narayana Murty N <nnmlinux@linux.ibm.com> Reviewed-by: Vaibhav Jain <vaibhav@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240909140220.529333-1-nnmlinux@linux.ibm.com
2024-09-03arch, mm: move definition of node_data to generic codeMike Rapoport (Microsoft)
Every architecture that supports NUMA defines node_data in the same way: struct pglist_data *node_data[MAX_NUMNODES]; No reason to keep multiple copies of this definition and its forward declarations, especially when such forward declaration is the only thing in include/asm/mmzone.h for many architectures. Add definition and declaration of node_data to generic code and drop architecture-specific versions. Link: https://lkml.kernel.org/r/20240807064110.1003856-8-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Tested-by: Zi Yan <ziy@nvidia.com> # for x86_64 and arm64 Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [arm64 + CXL via QEMU] Acked-by: Dan Williams <dan.j.williams@intel.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Rob Herring (Arm) <robh@kernel.org> Cc: Samuel Holland <samuel.holland@sifive.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01mm: remove arch_unmap()Michael Ellerman
Now that powerpc no longer uses arch_unmap() to handle VDSO unmapping, there are no meaningful implementions left. Drop support for it entirely, and update comments which refer to it. Link: https://lkml.kernel.org/r/20240812082605.743814-3-mpe@ellerman.id.au Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Jeff Xu <jeffxu@google.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Pedro Falcato <pedro.falcato@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01powerpc/mm: handle VDSO unmapping via close() rather than arch_unmap()Michael Ellerman
Add a close() callback to the VDSO special mapping to handle unmapping of the VDSO. That will make it possible to remove the arch_unmap() hook entirely in a subsequent patch. Link: https://lkml.kernel.org/r/20240812082605.743814-2-mpe@ellerman.id.au Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Jeff Xu <jeffxu@google.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Pedro Falcato <pedro.falcato@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01mm/powerpc: add missing pud helpersPeter Xu
Some new helpers will be needed for pud entry updates soon. Introduce these helpers by referencing the pmd ones. Namely: - pudp_invalidate(): this helper invalidates a huge pud before a split happens, so that the invalidated pud entry will make sure no race will happen (either with software, like a concurrent zap, or hardware, like a/d bit lost). - pud_modify(): this helper applies a new pgprot to an existing huge pud mapping. For more information on why we need these two helpers, please refer to the corresponding pmd helpers in the mprotect() code path. Link: https://lkml.kernel.org/r/20240812181225.1360970-4-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Matthew Wilcox <willy@infradead.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rik van Riel <riel@surriel.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-08-30powerpc/pseries/dlpar: Remove device tree node for DLPAR IO removeHaren Myneni
In the powerpc-pseries specific implementation, the IO hotplug event is handled in the user space (drmgr tool). But update the device tree and /dev/mem access to allocate buffers for some RTAS calls are restricted when the kernel lockdown feature is enabled. For the DLPAR IO REMOVE, the corresponding device tree nodes and properties have to be removed from the device tree after the device disable. The user space removes the device tree nodes by updating /proc/ppc64/ofdt which is not allowed under system lockdown is enabled. This restriction can be resolved by moving the complete IO hotplug handling in the kernel. But the pseries implementation need user interaction to power off and to remove device from the slot during hotplug event handling. To overcome the /proc/ppc64/ofdt restriction, this patch extends the /sys/kernel/dlpar interface and provides ‘dt remove index <drc_index>’ to the user space so that drmgr tool can remove the corresponding device tree nodes based on DRC index from the device tree. Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com> Signed-off-by: Haren Myneni <haren@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240822025028.938332-2-haren@linux.ibm.com
2024-08-30powerpc/32: Implement validation of emergency stackChristophe Leroy
VMAP stack added an emergency stack on powerpc/32 for when there is a stack overflow, but failed to add stack validation for that emergency stack. That validation is required for show stack. Implement it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/2439d50b019f758db4a6d7b238b06441ab109799.1724156805.git.christophe.leroy@csgroup.eu
2024-08-30powerpc/603: Copy kernel PGD entries into all PGDIRs and preallocate execmem ↵Christophe Leroy
page tables For the same reason as 8xx, copy kernel PGD entries into all PGDIRs in pgd_alloc() and preallocate execmem page tables before creating new PGDs so that all PGD entries related to execmem are copied by pgd_alloc(). This will help reduce the fast-path in TLBmiss handlers. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/1a0d1feee07c4cf955f6a43a704c203e5c90fa53.1724173828.git.christophe.leroy@csgroup.eu
2024-08-30powerpc/32s: Reduce default size of module/execmem areaChristophe Leroy
book3s/32 platforms have usually more memory than 8xx, but it is still not worth reserving a full segment (256 Mbytes) for module text. 64Mbytes should be far enough. Also fix TASK_SIZE when EXECMEM is not selected, and add a build verification for overlap of module execmem space with user segments. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/c1f6a4e47f177d919561c6e97d31af5564923cf6.1724173828.git.christophe.leroy@csgroup.eu
2024-08-30powerpc/8xx: Reduce default size of module/execmem areaChristophe Leroy
8xx boards don't have much memory, the two I know have respectively 32Mbytes and 128Mbytes, so there is no point in having 256 Mbytes of memory for module text. Reduce it to 32Mbytes for 8xx, that's more than enough. Nevertheless, make it a configurable value so that it can be customised if needed. Also add a build verification for overlap of module execmem space with user PMD. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/8db23b61e33a0d1913d814f94bfe71ba7ac78b0f.1724173828.git.christophe.leroy@csgroup.eu
2024-08-30powerpc/8xx: Copy kernel PGD entries into all PGDIRsChristophe Leroy
In order to avoid having to select PGDIR at each TLB miss based on fault address, copy kernel PGD entries into all PGDIRs in pgd_alloc(). At first it will be used for ITLB misses for kernel TEXT, then for execmem then for kernel DATA. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/c6d2bf5af2ea909071a85bdca8b1f5dc2df134a8.1724173828.git.christophe.leroy@csgroup.eu
2024-08-30powerpc: Remove obsoleted declarations for use_cop and drop_copGaosheng Cui
The use_cop() and drop_cop() have been removed since commit 6ff4d3e96652 ("powerpc: Remove old unused icswx based coprocessor support"), now they are useless, so remove them. Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240822130609.786431-5-cuigaosheng1@huawei.com
2024-08-29powerpc/64s/mm: Move __real_pte stubs into hash-4k.hMichael Ellerman
The stub versions of __real_pte() etc are only used with HPT & 4K pages, so move them into the hash-4k.h header. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240821080729.872034-1-mpe@ellerman.id.au
2024-08-22powerpc/mm: Fix return type of pgd_val()Christophe Leroy
Commit 6b0e82791bd0 ("powerpc/e500: switch to 64 bits PGD on 85xx (32 bits)") switched PGD entries to 64 bits, but pgd_val() returns an unsigned long which is 32 bits on PPC32. This is not a problem for regular PMD entries because the upper part is always NULL, but when PMD entries are leaf they contain 64 bits values, so pgd_val() must return an unsigned long long instead of an unsigned long. Also change the condition to CONFIG_PPC_85xx instead of CONFIG_PPC_E500 as the change was meant for 32 bits only. Allthough this should be harmless on PPC64, it generates a warning with pgd_ERROR print. Fixes: 6b0e82791bd0 ("powerpc/e500: switch to 64 bits PGD on 85xx (32 bits)") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/45f8fdf298ec3df7573b66d21b03a5cda92e2cb1.1724313510.git.christophe.leroy@csgroup.eu
2024-08-21powerpc/code-patching: Add data patch alignment checkBenjamin Gray
The new data patching still needs to be aligned within a cacheline too for the flushes to work correctly. To simplify this requirement, we just say data patches must be aligned. Detect when data patching is not aligned, returning an invalid argument error. Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Reviewed-by: Hari Bathini <hbathini@linux.ibm.com> Acked-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240515024445.236364-3-bgray@linux.ibm.com
2024-08-21powerpc/code-patching: Add generic memory patchingBenjamin Gray
patch_instruction() is designed for patching instructions in otherwise readonly memory. Other consumers also sometimes need to patch readonly memory, so have abused patch_instruction() for arbitrary data patches. This is a problem on ppc64 as patch_instruction() decides on the patch width using the 'instruction' opcode to see if it's a prefixed instruction. Data that triggers this can lead to larger writes, possibly crossing a page boundary and failing the write altogether. Introduce patch_uint(), and patch_ulong(), with aliases patch_u32(), and patch_u64() (on ppc64) designed for aligned data patches. The patch size is now determined by the called function, and is passed as an additional parameter to generic internals. While the instruction flushing is not required for data patches, it remains unconditional in this patch. A followup series is possible if benchmarking shows fewer flushes gives an improvement in some data-patching workload. ppc32 does not support prefixed instructions, so is unaffected by the original issue. Care is taken in not exposing the size parameter in the public (non-static) interface, so the compiler can const-propagate it away. Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Reviewed-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240515024445.236364-2-bgray@linux.ibm.com
2024-08-21powerpc: Remove unused LHZX_BE macroChristophe Leroy
LHZX_BE has been unused since commit dbf44daf7c88 ("bpf, ppc64: remove ld_abs/ld_ind") Remove it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/fd332b01c47bb9cb6c3af1696a2e109be655f5b5.1724222856.git.christophe.leroy@csgroup.eu
2024-08-13powerpc/topology: Check if a core is onlineNysal Jan K.A
topology_is_core_online() checks if the core a CPU belongs to is online. The core is online if at least one of the sibling CPUs is online. The first CPU of an online core is also online in the common case, so this should be fairly quick. Fixes: 73c58e7e1412 ("powerpc: Add HOTPLUG_SMT support") Signed-off-by: Nysal Jan K.A <nysal@linux.ibm.com> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240731030126.956210-3-nysal@linux.ibm.com
2024-08-07powerpc: Remove useless config comment in asm/percpu.hJinjie Ruan
commit 0db880fc865f ("powerpc: Avoid nmi_enter/nmi_exit in real mode interrupt.") has a config comment typo, and the #if/#else/#endif section is small and doesn't nest additional #ifdefs so the comment is useless and should be removed completely. Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240807025604.2817577-1-ruanjinjie@huawei.com