kernel.git/arch/powerpc/platforms/pseries, branch linux-5.10.y

powerpc/pseries/cmm: adjust BALLOON_MIGRATE when migrating pages

2026-01-19T12:12:05Z

[ Upstream commit 0da2ba35c0d532ca0fe7af698b17d74c4d084b9a ] Let's properly adjust BALLOON_MIGRATE like the other drivers. Note that the INFLATE/DEFLATE events are triggered from the core when enqueueing/dequeueing pages. This was found by code inspection. Link: https://lkml.kernel.org/r/20251021100606.148294-3-david@redhat.com Fixes: fe030c9b85e6 ("powerpc/pseries/cmm: Implement balloon compaction") Signed-off-by: David Hildenbrand Reviewed-by: Ritesh Harjani (IBM) Cc: Christophe Leroy Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

mm/balloon_compaction: convert balloon_page_delete() to balloon_page_finalize()

2026-01-19T12:12:05Z

[ Upstream commit 15504b1163007bbfbd9a63460d5c14737c16e96d ] Let's move the removal of the page from the balloon list into the single caller, to remove the dependency on the PG_isolated flag and clarify locking requirements. Note that for now, balloon_page_delete() was used on two paths: (1) Removing a page from the balloon for deflation through balloon_page_list_dequeue() (2) Removing an isolated page from the balloon for migration in the per-driver migration handlers. Isolated pages were already removed from the balloon list during isolation. So instead of relying on the flag, we can just distinguish both cases directly and handle it accordingly in the caller. We'll shuffle the operations a bit such that they logically make more sense (e.g., remove from the list before clearing flags). In balloon migration functions we can now move the balloon_page_finalize() out of the balloon lock and perform the finalization just before dropping the balloon reference. Document that the page lock is currently required when modifying the movability aspects of a page; hopefully we can soon decouple this from the page lock. Link: https://lkml.kernel.org/r/20250704102524.326966-3-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Lorenzo Stoakes Cc: Alistair Popple Cc: Al Viro Cc: Arnd Bergmann Cc: Brendan Jackman Cc: Byungchul Park Cc: Chengming Zhou Cc: Christian Brauner Cc: Christophe Leroy Cc: Eugenio Pé rez Cc: Greg Kroah-Hartman Cc: Gregory Price Cc: Harry Yoo Cc: "Huang, Ying" Cc: Jan Kara Cc: Jason Gunthorpe Cc: Jason Wang Cc: Jerrin Shaji George Cc: Johannes Weiner Cc: John Hubbard Cc: Jonathan Corbet Cc: Joshua Hahn Cc: Liam Howlett Cc: Madhavan Srinivasan Cc: Mathew Brost Cc: Matthew Wilcox (Oracle) Cc: Miaohe Lin Cc: Michael Ellerman Cc: "Michael S. Tsirkin" Cc: Michal Hocko Cc: Mike Rapoport Cc: Minchan Kim Cc: Naoya Horiguchi Cc: Nicholas Piggin Cc: Oscar Salvador Cc: Peter Xu Cc: Qi Zheng Cc: Rakie Kim Cc: Rik van Riel Cc: Sergey Senozhatsky Cc: Shakeel Butt Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Xuan Zhuo Cc: xu xin Cc: Zi Yan Signed-off-by: Andrew Morton Stable-dep-of: 0da2ba35c0d5 ("powerpc/pseries/cmm: adjust BALLOON_MIGRATE when migrating pages") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

powerpc/pseries/cmm: call balloon_devinfo_init() also without CONFIG_BALLOON_COMPACTION

2026-01-19T12:12:04Z

[ Upstream commit fc6bcf9ac4de76f5e7bcd020b3c0a86faff3f2d5 ] Patch series "powerpc/pseries/cmm: two smaller fixes". Two smaller fixes identified while doing a bigger rework. This patch (of 2): We always have to initialize the balloon_dev_info, even when compaction is not configured in: otherwise the containing list and the lock are left uninitialized. Likely not many such configs exist in practice, but let's CC stable to be sure. This was found by code inspection. Link: https://lkml.kernel.org/r/20251021100606.148294-1-david@redhat.com Link: https://lkml.kernel.org/r/20251021100606.148294-2-david@redhat.com Fixes: fe030c9b85e6 ("powerpc/pseries/cmm: Implement balloon compaction") Signed-off-by: David Hildenbrand Reviewed-by: Ritesh Harjani (IBM) Cc: Christophe Leroy Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Signed-off-by: Andrew Morton [ moved balloon_devinfo_init() call from inside cmm_balloon_compaction_init() to cmm_init() ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

powerpc/pseries/eeh: Fix get PE state translation

2025-03-13T11:47:09Z

commit 11b93559000c686ad7e5ab0547e76f21cc143844 upstream. The PE Reset State "0" returned by RTAS calls "ibm_read_slot_reset_[state|state2]" indicates that the reset is deactivated and the PE is in a state where MMIO and DMA are allowed. However, the current implementation of "pseries_eeh_get_state()" does not reflect this, causing drivers to incorrectly assume that MMIO and DMA operations cannot be resumed. The userspace drivers as a part of EEH recovery using VFIO ioctls fail to detect when the recovery process is complete. The VFIO_EEH_PE_GET_STATE ioctl does not report the expected EEH_PE_STATE_NORMAL state, preventing userspace drivers from functioning properly on pseries systems. The patch addresses this issue by updating 'pseries_eeh_get_state()' to include "EEH_STATE_MMIO_ENABLED" and "EEH_STATE_DMA_ENABLED" in the result mask for PE Reset State "0". This ensures correct state reporting to the callers, aligning the behavior with the PAPR specification and fixing the bug in EEH recovery for VFIO user workflows. Fixes: 00ba05a12b3c ("powerpc/pseries: Cleanup on pseries_eeh_get_state()") Cc: stable@vger.kernel.org Reviewed-by: Ritesh Harjani (IBM) Signed-off-by: Narayana Murty N Link: https://lore.kernel.org/stable/20241212075044.10563-1-nnmlinux%40linux.ibm.com Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/20250116103954.17324-1-nnmlinux@linux.ibm.com Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Fix dtl_access_lock to be a rw_semaphore

2024-12-14T18:47:58Z

[ Upstream commit cadae3a45d23aa4f6485938a67cbc47aaaa25e38 ] 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 Reviewed-by: Nysal Jan K.A Reviewed-by: Kajol Jain Signed-off-by: Michael Ellerman Link: https://patch.msgid.link/20240819122401.513203-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin

powerpc/pseries: Whitelist dtl slub object for copying to userspace

2024-07-27T08:40:21Z

[ Upstream commit 1a14150e1656f7a332a943154fc486504db4d586 ] Reading the dispatch trace log from /sys/kernel/debug/powerpc/dtl/cpu-* results in a BUG() when the config CONFIG_HARDENED_USERCOPY is enabled as shown below. kernel BUG at mm/usercopy.c:102! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries Modules linked in: xfs libcrc32c dm_service_time sd_mod t10_pi sg ibmvfc scsi_transport_fc ibmveth pseries_wdt dm_multipath dm_mirror dm_region_hash dm_log dm_mod fuse CPU: 27 PID: 1815 Comm: python3 Not tainted 6.10.0-rc3 #85 Hardware name: IBM,9040-MRX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NM1060_042) hv:phyp pSeries NIP: c0000000005d23d4 LR: c0000000005d23d0 CTR: 00000000006ee6f8 REGS: c000000120c078c0 TRAP: 0700 Not tainted (6.10.0-rc3) MSR: 8000000000029033 CR: 2828220f XER: 0000000e CFAR: c0000000001fdc80 IRQMASK: 0 [ ... GPRs omitted ... ] NIP [c0000000005d23d4] usercopy_abort+0x78/0xb0 LR [c0000000005d23d0] usercopy_abort+0x74/0xb0 Call Trace: usercopy_abort+0x74/0xb0 (unreliable) __check_heap_object+0xf8/0x120 check_heap_object+0x218/0x240 __check_object_size+0x84/0x1a4 dtl_file_read+0x17c/0x2c4 full_proxy_read+0x8c/0x110 vfs_read+0xdc/0x3a0 ksys_read+0x84/0x144 system_call_exception+0x124/0x330 system_call_vectored_common+0x15c/0x2ec --- interrupt: 3000 at 0x7fff81f3ab34 Commit 6d07d1cd300f ("usercopy: Restrict non-usercopy caches to size 0") requires that only whitelisted areas in slab/slub objects can be copied to userspace when usercopy hardening is enabled using CONFIG_HARDENED_USERCOPY. Dtl contains hypervisor dispatch events which are expected to be read by privileged users. Hence mark this safe for user access. Specify useroffset=0 and usersize=DISPATCH_LOG_BYTES to whitelist the entire object. Co-developed-by: Vishal Chourasia Signed-off-by: Vishal Chourasia Signed-off-by: Anjali K Reviewed-by: Srikar Dronamraju Signed-off-by: Michael Ellerman Link: https://msgid.link/20240614173844.746818-1-anjalik@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/pseries: Add failure related checks for h_get_mpp and h_get_ppp

2024-06-16T11:32:24Z

[ Upstream commit 6d4341638516bf97b9a34947e0bd95035a8230a5 ] Couple of Minor fixes: - hcall return values are long. Fix that for h_get_mpp, h_get_ppp and parse_ppp_data - If hcall fails, values set should be at-least zero. It shouldn't be uninitialized values. Fix that for h_get_mpp and h_get_ppp Signed-off-by: Shrikanth Hegde Signed-off-by: Michael Ellerman Link: https://msgid.link/20240412092047.455483-3-sshegde@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/pseries/memhp: Fix access beyond end of drmem array

2024-01-25T22:37:39Z

[ Upstream commit bd68ffce69f6cf8ddd3a3c32549d1d2275e49fc5 ] dlpar_memory_remove_by_index() may access beyond the bounds of the drmem lmb array when the LMB lookup fails to match an entry with the given DRC index. When the search fails, the cursor is left pointing to &drmem_info->lmbs[drmem_info->n_lmbs], which is one element past the last valid entry in the array. The debug message at the end of the function then dereferences this pointer: pr_debug("Failed to hot-remove memory at %llx\n", lmb->base_addr); This was found by inspection and confirmed with KASAN: pseries-hotplug-mem: Attempting to hot-remove LMB, drc index 1234 ================================================================== BUG: KASAN: slab-out-of-bounds in dlpar_memory+0x298/0x1658 Read of size 8 at addr c000000364e97fd0 by task bash/949 dump_stack_lvl+0xa4/0xfc (unreliable) print_report+0x214/0x63c kasan_report+0x140/0x2e0 __asan_load8+0xa8/0xe0 dlpar_memory+0x298/0x1658 handle_dlpar_errorlog+0x130/0x1d0 dlpar_store+0x18c/0x3e0 kobj_attr_store+0x68/0xa0 sysfs_kf_write+0xc4/0x110 kernfs_fop_write_iter+0x26c/0x390 vfs_write+0x2d4/0x4e0 ksys_write+0xac/0x1a0 system_call_exception+0x268/0x530 system_call_vectored_common+0x15c/0x2ec Allocated by task 1: kasan_save_stack+0x48/0x80 kasan_set_track+0x34/0x50 kasan_save_alloc_info+0x34/0x50 __kasan_kmalloc+0xd0/0x120 __kmalloc+0x8c/0x320 kmalloc_array.constprop.0+0x48/0x5c drmem_init+0x2a0/0x41c do_one_initcall+0xe0/0x5c0 kernel_init_freeable+0x4ec/0x5a0 kernel_init+0x30/0x1e0 ret_from_kernel_user_thread+0x14/0x1c The buggy address belongs to the object at c000000364e80000 which belongs to the cache kmalloc-128k of size 131072 The buggy address is located 0 bytes to the right of allocated 98256-byte region [c000000364e80000, c000000364e97fd0) ================================================================== pseries-hotplug-mem: Failed to hot-remove memory at 0 Log failed lookups with a separate message and dereference the cursor only when it points to a valid entry. Signed-off-by: Nathan Lynch Fixes: 51925fb3c5c9 ("powerpc/pseries: Implement memory hotplug remove in the kernel") Signed-off-by: Michael Ellerman Link: https://msgid.link/20231114-pseries-memhp-fixes-v1-1-fb8f2bb7c557@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/pseries/memhotplug: Quieten some DLPAR operations

2024-01-25T22:37:39Z

[ Upstream commit 20e9de85edae3a5866f29b6cce87c9ec66d62a1b ] When attempting to remove by index a set of LMBs a lot of messages are displayed on the console, even when everything goes fine: pseries-hotplug-mem: Attempting to hot-remove LMB, drc index 8000002d Offlined Pages 4096 pseries-hotplug-mem: Memory at 2d0000000 was hot-removed The 2 messages prefixed by "pseries-hotplug-mem" are not really helpful for the end user, they should be debug outputs. In case of error, because some of the LMB's pages couldn't be offlined, the following is displayed on the console: pseries-hotplug-mem: Attempting to hot-remove LMB, drc index 8000003e pseries-hotplug-mem: Failed to hot-remove memory at 3e0000000 dlpar: Could not handle DLPAR request "memory remove index 0x8000003e" Again, the 2 messages prefixed by "pseries-hotplug-mem" are useless, and the generic DLPAR prefixed message should be enough. These 2 first changes are mainly triggered by the changes introduced in drmgr: https://groups.google.com/g/powerpc-utils-devel/c/Y6ef4NB3EzM/m/9cu5JHRxAQAJ Also, when adding a bunch of LMBs, a message is displayed in the console per LMB like these ones: pseries-hotplug-mem: Memory at 7e0000000 (drc index 8000007e) was hot-added pseries-hotplug-mem: Memory at 7f0000000 (drc index 8000007f) was hot-added pseries-hotplug-mem: Memory at 800000000 (drc index 80000080) was hot-added pseries-hotplug-mem: Memory at 810000000 (drc index 80000081) was hot-added When adding 1TB of memory and LMB size is 256MB, this leads to 4096 messages to be displayed on the console. These messages are not really helpful for the end user, so moving them to the DEBUG level. Signed-off-by: Laurent Dufour [mpe: Tweak change log wording] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201211145954.90143-1-ldufour@linux.ibm.com Stable-dep-of: bd68ffce69f6 ("powerpc/pseries/memhp: Fix access beyond end of drmem array") Signed-off-by: Sasha Levin

powerpc/pseries: fix potential memory leak in init_cpu_associativity()

2023-11-20T10:06:54Z

[ Upstream commit 95f1a128cd728a7257d78e868f1f5a145fc43736 ] If the vcpu_associativity alloc memory successfully but the pcpu_associativity fails to alloc memory, the vcpu_associativity memory leaks. Fixes: d62c8deeb6e6 ("powerpc/pseries: Provide vcpu dispatch statistics") Signed-off-by: Wang Yufen Reviewed-by: "Naveen N. Rao" Signed-off-by: Michael Ellerman Link: https://msgid.link/1671003983-10794-1-git-send-email-wangyufen@huawei.com Signed-off-by: Sasha Levin