summaryrefslogtreecommitdiff
path: root/include
AgeCommit message (Collapse)Author
2025-08-28iopoll: Reorder the timeout handling in poll_timeout_us()Ville Syrjälä
Currently poll_timeout_us() evaluates 'op' and 'cond' twice within the loop, once at the start, and a second time after the timeout check. While it's probably not a big deal to do it twice almost back to back, it does make the macro a bit messy. Simplify the implementation to evaluate the timeout at the very start, then follow up with 'op'/'cond', and finally check if the timeout did in fact happen or not. For good measure throw in a compiler barrier between the timeout and 'op'/'cond' evaluations to make sure the compiler can't reoder the operations (which could cause false positive timeouts). The similar i915 __wait_for() macro already has the barrier, though there it is between the 'op' and 'cond' evaluations, which seems like it could still allow 'op' and the timeout evaluations to get reordered incorrectly. I suppose the ktime_get() might itself act as a sufficient barrier here, but better safe than sorry I guess. Cc: Lucas De Marchi <lucas.demarchi@intel.com> Cc: Dibin Moolakadan Subrahmanian <dibin.moolakadan.subrahmanian@intel.com> Cc: Imre Deak <imre.deak@intel.com> Cc: David Laight <david.laight.linux@gmail.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Matt Wagantall <mattw@codeaurora.org> Cc: Dejin Zheng <zhengdejin5@gmail.com> Cc: intel-gfx@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Simona Vetter <simona.vetter@ffwll.ch> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://lore.kernel.org/r/20250826121859.15497-3-ville.syrjala@linux.intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2025-08-28iopoll: Avoid evaluating 'cond' twice in poll_timeout_us()Ville Syrjälä
Currently poll_timeout_us() evaluates 'cond' twice at the end of the success case. This not desirable in case 'cond' itself is expensive. Avoid the double evaluation by tracking the return value in a variable. Need to use a triple undescore '___ret' name to avoid a conflict with an existing double undescore '__ret' variable in the regmap code. Cc: Lucas De Marchi <lucas.demarchi@intel.com> Cc: Dibin Moolakadan Subrahmanian <dibin.moolakadan.subrahmanian@intel.com> Cc: Imre Deak <imre.deak@intel.com> Cc: David Laight <david.laight.linux@gmail.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Matt Wagantall <mattw@codeaurora.org> Cc: Dejin Zheng <zhengdejin5@gmail.com> Cc: intel-gfx@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Simona Vetter <simona.vetter@ffwll.ch> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://lore.kernel.org/r/20250826121859.15497-2-ville.syrjala@linux.intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2025-08-28iopoll: Generalize read_poll_timeout() into poll_timeout_us()Ville Syrjälä
While read_poll_timeout() & co. were originally introduced just for simple I/O usage scenarios they have since been generalized to be useful in more cases. However the interface is very cumbersome to use in the general case. Attempt to make it more flexible by combining the 'op', 'var' and 'args' parameter into just a single 'op' that the caller can fully specify. For example i915 has one case where one might currently have to write something like: ret = read_poll_timeout(drm_dp_dpcd_read_byte, err, err || (status & mask), 0 * 1000, 200 * 1000, false, aux, DP_FEC_STATUS, &status); which is practically illegible, but with the adjusted macro we do: ret = poll_timeout_us(err = drm_dp_dpcd_read_byte(aux, DP_FEC_STATUS, &status), err || (status & mask), 0 * 1000, 200 * 1000, false); which much easier to understand. One could even combine the 'op' and 'cond' parameters into one, but that might make the caller a bit too unwieldly with assignments and checks being done on the same statement. This makes poll_timeout_us() closer to the i915 __wait_for() macro, with the main difference being that __wait_for() uses expenential backoff as opposed to the fixed polling interval used by poll_timeout_us(). Eventually we might be able to switch (at least most of) i915 to use poll_timeout_us(). v2: Fix typos (Jani) Fix delay_us docs for poll_timeout_us_atomic() (Jani) Cc: Lucas De Marchi <lucas.demarchi@intel.com> Cc: Dibin Moolakadan Subrahmanian <dibin.moolakadan.subrahmanian@intel.com> Cc: Imre Deak <imre.deak@intel.com> Cc: David Laight <david.laight.linux@gmail.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Matt Wagantall <mattw@codeaurora.org> Cc: Dejin Zheng <zhengdejin5@gmail.com> Cc: intel-gfx@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Simona Vetter <simona.vetter@ffwll.ch> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://lore.kernel.org/r/20250826121859.15497-1-ville.syrjala@linux.intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2025-08-27mm: introduce and use {pgd,p4d}_populate_kernel()Harry Yoo
Introduce and use {pgd,p4d}_populate_kernel() in core MM code when populating PGD and P4D entries for the kernel address space. These helpers ensure proper synchronization of page tables when updating the kernel portion of top-level page tables. Until now, the kernel has relied on each architecture to handle synchronization of top-level page tables in an ad-hoc manner. For example, see commit 9b861528a801 ("x86-64, mem: Update all PGDs for direct mapping and vmemmap mapping changes"). However, this approach has proven fragile for following reasons: 1) It is easy to forget to perform the necessary page table synchronization when introducing new changes. For instance, commit 4917f55b4ef9 ("mm/sparse-vmemmap: improve memory savings for compound devmaps") overlooked the need to synchronize page tables for the vmemmap area. 2) It is also easy to overlook that the vmemmap and direct mapping areas must not be accessed before explicit page table synchronization. For example, commit 8d400913c231 ("x86/vmemmap: handle unpopulated sub-pmd ranges")) caused crashes by accessing the vmemmap area before calling sync_global_pgds(). To address this, as suggested by Dave Hansen, introduce _kernel() variants of the page table population helpers, which invoke architecture-specific hooks to properly synchronize page tables. These are introduced in a new header file, include/linux/pgalloc.h, so they can be called from common code. They reuse existing infrastructure for vmalloc and ioremap. Synchronization requirements are determined by ARCH_PAGE_TABLE_SYNC_MASK, and the actual synchronization is performed by arch_sync_kernel_mappings(). This change currently targets only x86_64, so only PGD and P4D level helpers are introduced. Currently, these helpers are no-ops since no architecture sets PGTBL_{PGD,P4D}_MODIFIED in ARCH_PAGE_TABLE_SYNC_MASK. In theory, PUD and PMD level helpers can be added later if needed by other architectures. For now, 32-bit architectures (x86-32 and arm) only handle PGTBL_PMD_MODIFIED, so p*d_populate_kernel() will never affect them unless we introduce a PMD level helper. [harry.yoo@oracle.com: fix KASAN build error due to p*d_populate_kernel()] Link: https://lkml.kernel.org/r/20250822020727.202749-1-harry.yoo@oracle.com Link: https://lkml.kernel.org/r/20250818020206.4517-3-harry.yoo@oracle.com Fixes: 8d400913c231 ("x86/vmemmap: handle unpopulated sub-pmd ranges") Signed-off-by: Harry Yoo <harry.yoo@oracle.com> Suggested-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Kiryl Shutsemau <kas@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: bibo mao <maobibo@loongson.cn> Cc: Borislav Betkov <bp@alien8.de> Cc: Christoph Lameter (Ampere) <cl@gentwo.org> Cc: Dennis Zhou <dennis@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Huth <thuth@redhat.com> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-08-27mm: move page table sync declarations to linux/pgtable.hHarry Yoo
During our internal testing, we started observing intermittent boot failures when the machine uses 4-level paging and has a large amount of persistent memory: BUG: unable to handle page fault for address: ffffe70000000034 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP NOPTI RIP: 0010:__init_single_page+0x9/0x6d Call Trace: <TASK> __init_zone_device_page+0x17/0x5d memmap_init_zone_device+0x154/0x1bb pagemap_range+0x2e0/0x40f memremap_pages+0x10b/0x2f0 devm_memremap_pages+0x1e/0x60 dev_dax_probe+0xce/0x2ec [device_dax] dax_bus_probe+0x6d/0xc9 [... snip ...] </TASK> It turns out that the kernel panics while initializing vmemmap (struct page array) when the vmemmap region spans two PGD entries, because the new PGD entry is only installed in init_mm.pgd, but not in the page tables of other tasks. And looking at __populate_section_memmap(): if (vmemmap_can_optimize(altmap, pgmap)) // does not sync top level page tables r = vmemmap_populate_compound_pages(pfn, start, end, nid, pgmap); else // sync top level page tables in x86 r = vmemmap_populate(start, end, nid, altmap); In the normal path, vmemmap_populate() in arch/x86/mm/init_64.c synchronizes the top level page table (See commit 9b861528a801 ("x86-64, mem: Update all PGDs for direct mapping and vmemmap mapping changes")) so that all tasks in the system can see the new vmemmap area. However, when vmemmap_can_optimize() returns true, the optimized path skips synchronization of top-level page tables. This is because vmemmap_populate_compound_pages() is implemented in core MM code, which does not handle synchronization of the top-level page tables. Instead, the core MM has historically relied on each architecture to perform this synchronization manually. We're not the first party to encounter a crash caused by not-sync'd top level page tables: earlier this year, Gwan-gyeong Mun attempted to address the issue [1] [2] after hitting a kernel panic when x86 code accessed the vmemmap area before the corresponding top-level entries were synced. At that time, the issue was believed to be triggered only when struct page was enlarged for debugging purposes, and the patch did not get further updates. It turns out that current approach of relying on each arch to handle the page table sync manually is fragile because 1) it's easy to forget to sync the top level page table, and 2) it's also easy to overlook that the kernel should not access the vmemmap and direct mapping areas before the sync. # The solution: Make page table sync more code robust and harder to miss To address this, Dave Hansen suggested [3] [4] introducing {pgd,p4d}_populate_kernel() for updating kernel portion of the page tables and allow each architecture to explicitly perform synchronization when installing top-level entries. With this approach, we no longer need to worry about missing the sync step, reducing the risk of future regressions. The new interface reuses existing ARCH_PAGE_TABLE_SYNC_MASK, PGTBL_P*D_MODIFIED and arch_sync_kernel_mappings() facility used by vmalloc and ioremap to synchronize page tables. pgd_populate_kernel() looks like this: static inline void pgd_populate_kernel(unsigned long addr, pgd_t *pgd, p4d_t *p4d) { pgd_populate(&init_mm, pgd, p4d); if (ARCH_PAGE_TABLE_SYNC_MASK & PGTBL_PGD_MODIFIED) arch_sync_kernel_mappings(addr, addr); } It is worth noting that vmalloc() and apply_to_range() carefully synchronizes page tables by calling p*d_alloc_track() and arch_sync_kernel_mappings(), and thus they are not affected by this patch series. This series was hugely inspired by Dave Hansen's suggestion and hence added Suggested-by: Dave Hansen. Cc stable because lack of this series opens the door to intermittent boot failures. This patch (of 3): Move ARCH_PAGE_TABLE_SYNC_MASK and arch_sync_kernel_mappings() to linux/pgtable.h so that they can be used outside of vmalloc and ioremap. Link: https://lkml.kernel.org/r/20250818020206.4517-1-harry.yoo@oracle.com Link: https://lkml.kernel.org/r/20250818020206.4517-2-harry.yoo@oracle.com Link: https://lore.kernel.org/linux-mm/20250220064105.808339-1-gwan-gyeong.mun@intel.com [1] Link: https://lore.kernel.org/linux-mm/20250311114420.240341-1-gwan-gyeong.mun@intel.com [2] Link: https://lore.kernel.org/linux-mm/d1da214c-53d3-45ac-a8b6-51821c5416e4@intel.com [3] Link: https://lore.kernel.org/linux-mm/4d800744-7b88-41aa-9979-b245e8bf794b@intel.com [4] Fixes: 8d400913c231 ("x86/vmemmap: handle unpopulated sub-pmd ranges") Signed-off-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Kiryl Shutsemau <kas@kernel.org> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: bibo mao <maobibo@loongson.cn> Cc: Borislav Betkov <bp@alien8.de> Cc: Christoph Lameter (Ampere) <cl@gentwo.org> Cc: Dennis Zhou <dennis@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Huth <thuth@redhat.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-08-27kexec: add KEXEC_FILE_NO_CMA as a legal flagBrian Mak
Commit 07d24902977e ("kexec: enable CMA based contiguous allocation") introduces logic to use CMA-based allocation in kexec by default. As part of the changes, it introduces a kexec_file_load flag to disable the use of CMA allocations from userspace. However, this flag is broken since it is missing from the list of legal flags for kexec_file_load. kexec_file_load returns EINVAL when attempting to use the flag. Fix this by adding the KEXEC_FILE_NO_CMA flag to the list of legal flags for kexec_file_load. Without this fix, kexec_file_load syscall will failed and return '-EINVAL' when KEXEC_FILE_NO_CMA is specified. Link: https://lkml.kernel.org/r/20250805211527.122367-2-makb@juniper.net Fixes: 07d24902977e ("kexec: enable CMA based contiguous allocation") Signed-off-by: Brian Mak <makb@juniper.net> Acked-by: Baoquan He <bhe@redhat.com> Cc: Alexander Graf <graf@amazon.com> Cc: Borislav Betkov <bp@alien8.de> Cc: Dave Young <dyoung@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Thomas Gleinxer <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-08-27net: Prevent RPS table overwrite of active flowsKrishna Kumar
This patch fixes an issue where two different flows on the same RXq produce the same hash resulting in continuous flow overwrites. Flow #1: A packet for Flow #1 comes in, kernel calls the steering function. The driver gives back a filter id. The kernel saves this filter id in the selected slot. Later, the driver's service task checks if any filters have expired and then installs the rule for Flow #1. Flow #2: A packet for Flow #2 comes in. It goes through the same steps. But this time, the chosen slot is being used by Flow #1. The driver gives a new filter id and the kernel saves it in the same slot. When the driver's service task runs, it runs through all the flows, checks if Flow #1 should be expired, the kernel returns True as the slot has a different filter id, and then the driver installs the rule for Flow #2. Flow #1: Another packet for Flow #1 comes in. The same thing repeats. The slot is overwritten with a new filter id for Flow #1. This causes a repeated cycle of flow programming for missed packets, wasting CPU cycles while not improving performance. This problem happens at higher rates when the RPS table is small, but tests show it still happens even with 12,000 connections and an RPS size of 16K per queue (global table size = 144x16K = 64K). This patch prevents overwriting an rps_dev_flow entry if it is active. The intention is that it is better to do aRFS for the first flow instead of hurting all flows on the same hash. Without this, two (or more) flows on one RX queue with the same hash can keep overwriting each other. This causes the driver to reprogram the flow repeatedly. Changes: 1. Add a new 'hash' field to struct rps_dev_flow. 2. Add rps_flow_is_active(): a helper function to check if a flow is active or not, extracted from rps_may_expire_flow(). It is further simplified as per reviewer feedback. 3. In set_rps_cpu(): - Avoid overwriting by programming a new filter if: - The slot is not in use, or - The slot is in use but the flow is not active, or - The slot has an active flow with the same hash, but target CPU differs. - Save the hash in the rps_dev_flow entry. 4. rps_may_expire_flow(): Use earlier extracted rps_flow_is_active(). Testing & results: - Driver: ice (E810 NIC), Kernel: net-next - #CPUs = #RXq = 144 (1:1) - Number of flows: 12K - Eight RPS settings from 256 to 32768. Though RPS=256 is not ideal, it is still sufficient to cover 12K flows (256*144 rx-queues = 64K global table slots) - Global Table Size = 144 * RPS (effectively equal to 256 * RPS) - Each RPS test duration = 8 mins (org code) + 8 mins (new code). - Metrics captured on client Legend for following tables: Steer-C: #times ndo_rx_flow_steer() was Called by set_rps_cpu() Steer-L: #times ice_arfs_flow_steer() Looped over aRFS entries Add: #times driver actually programmed aRFS (ice_arfs_build_entry()) Del: #times driver deleted the flow (ice_arfs_del_flow_rules()) Units: K = 1,000 times, M = 1 million times |-------|---------|------| Org Code |---------|---------| | RPS | Latency | CPU | Add | Del | Steer-C | Steer-L | |-------|---------|------|--------|--------|---------|---------| | 256 | 227.0 | 93.2 | 1.6M | 1.6M | 121.7M | 267.6M | | 512 | 225.9 | 94.1 | 11.5M | 11.2M | 65.7M | 199.6M | | 1024 | 223.5 | 95.6 | 16.5M | 16.5M | 27.1M | 187.3M | | 2048 | 222.2 | 96.3 | 10.5M | 10.5M | 12.5M | 115.2M | | 4096 | 223.9 | 94.1 | 5.5M | 5.5M | 7.2M | 65.9M | | 8192 | 224.7 | 92.5 | 2.7M | 2.7M | 3.0M | 29.9M | | 16384 | 223.5 | 92.5 | 1.3M | 1.3M | 1.4M | 13.9M | | 32768 | 219.6 | 93.2 | 838.1K | 838.1K | 965.1K | 8.9M | |-------|---------|------| New Code |---------|---------| | 256 | 201.5 | 99.1 | 13.4K | 5.0K | 13.7K | 75.2K | | 512 | 202.5 | 98.2 | 11.2K | 5.9K | 11.2K | 55.5K | | 1024 | 207.3 | 93.9 | 11.5K | 9.7K | 11.5K | 59.6K | | 2048 | 207.5 | 96.7 | 11.8K | 11.1K | 15.5K | 79.3K | | 4096 | 206.9 | 96.6 | 11.8K | 11.7K | 11.8K | 63.2K | | 8192 | 205.8 | 96.7 | 11.9K | 11.8K | 11.9K | 63.9K | | 16384 | 200.9 | 98.2 | 11.9K | 11.9K | 11.9K | 64.2K | | 32768 | 202.5 | 98.0 | 11.9K | 11.9K | 11.9K | 64.2K | |-------|---------|------|--------|--------|---------|---------| Some observations: 1. Overall Latency improved: (1790.19-1634.94)/1790.19*100 = 8.67% 2. Overall CPU increased: (777.32-751.49)/751.45*100 = 3.44% 3. Flow Management (add/delete) remained almost constant at ~11K compared to values in millions. Signed-off-by: Krishna Kumar <krikku@gmail.com> Link: https://patch.msgid.link/20250825031005.3674864-2-krikku@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-27bpf: Improve the general precision of tnum_mulNandakumar Edamana
Drop the value-mask decomposition technique and adopt straightforward long-multiplication with a twist: when LSB(a) is uncertain, find the two partial products (for LSB(a) = known 0 and LSB(a) = known 1) and take a union. Experiment shows that applying this technique in long multiplication improves the precision in a significant number of cases (at the cost of losing precision in a relatively lower number of cases). Signed-off-by: Nandakumar Edamana <nandakumar@nandakumar.co.in> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Harishankar Vishwanathan <harishankar.vishwanathan@gmail.com> Reviewed-by: Harishankar Vishwanathan <harishankar.vishwanathan@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20250826034524.2159515-1-nandakumar@nandakumar.co.in
2025-08-27io_uring/nop: add support for IORING_SETUP_CQE_MIXEDJens Axboe
This adds support for setting IORING_NOP_CQE32 as a flag for a NOP command, in which case a 32b CQE will be posted rather than a regular one. This is the default if the ring has been setup with IORING_SETUP_CQE32. If the ring has been setup with IORING_SETUP_CQE_MIXED, then 16b CQEs will be posted without this flag set, and 32b CQEs if this flag is set. For the latter case, sqe->off is what will be posted as cqe->big_cqe[0] and sqe->addr is what will be posted as cqe->big_cqe[1]. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-27io_uring: add support for IORING_SETUP_CQE_MIXEDJens Axboe
Normal rings support 16b CQEs for posting completions, while certain features require the ring to be configured with IORING_SETUP_CQE32, as they need to convey more information per completion. This, in turn, makes ALL the CQEs be 32b in size. This is somewhat wasteful and inefficient, particularly when only certain CQEs need to be of the bigger variant. This adds support for setting up a ring with mixed CQE sizes, using IORING_SETUP_CQE_MIXED. When setup in this mode, CQEs posted to the ring may be either 16b or 32b in size. If a CQE is 32b in size, then IORING_CQE_F_32 is set in the CQE flags to indicate that this is the case. If this flag isn't set, the CQE is the normal 16b variant. CQEs on these types of mixed rings may also have IORING_CQE_F_SKIP set. This can happen if the ring is one (small) CQE entry away from wrapping, and an attempt is made to post a 32b CQE. As CQEs must be contigious in the CQ ring, a 32b CQE cannot wrap the ring. For this case, a single dummy CQE is posted with the SKIP flag set. The application should simply ignore those. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-27Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio/vhost fixes from Michael Tsirkin: "More small fixes. Most notably this fixes a messed up ioctl number, and a regression in shmem affecting drm users" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: virtio_net: adjust the execution order of function `virtnet_close` during freeze virtio_input: Improve freeze handling vhost: Fix ioctl # for VHOST_[GS]ET_FORK_FROM_OWNER Revert "virtio: reject shm region if length is zero" vhost/net: Protect ubufs with rcu read lock in vhost_net_ubuf_put() virtio_pci: Fix misleading comment for queue vector
2025-08-27Merge tag 'media/v6.17-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media Pull media fixes from Mauro Carvalho Chehab: - drop the redundant pm_runtime_mark_last_busy() in rkvdec - fix probing error handling in rkvdec - fix an issue affecting lt6911uxe/lt6911uxc related to CSI-2 GPIO pins in int3472 * tag 'media/v6.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: media: Remove redundant pm_runtime_mark_last_busy() calls platform/x86: int3472: add hpd pin support media: rkvdec: Remove redundant pm_runtime_mark_last_busy() calls media: rkvdec: Fix an error handling path in rkvdec_probe() media: rkvdec: Fix a NULL vs IS_ERR() bug in probe()
2025-08-27net: rose: convert 'use' field to refcount_tTakamitsu Iwai
The 'use' field in struct rose_neigh is used as a reference counter but lacks atomicity. This can lead to race conditions where a rose_neigh structure is freed while still being referenced by other code paths. For example, when rose_neigh->use becomes zero during an ioctl operation via rose_rt_ioctl(), the structure may be removed while its timer is still active, potentially causing use-after-free issues. This patch changes the type of 'use' from unsigned short to refcount_t and updates all code paths to use rose_neigh_hold() and rose_neigh_put() which operate reference counts atomically. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Takamitsu Iwai <takamitz@amazon.co.jp> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250823085857.47674-3-takamitz@amazon.co.jp Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-27net: rose: split remove and free operations in rose_remove_neigh()Takamitsu Iwai
The current rose_remove_neigh() performs two distinct operations: 1. Removes rose_neigh from rose_neigh_list 2. Frees the rose_neigh structure Split these operations into separate functions to improve maintainability and prepare for upcoming refcount_t conversion. The timer cleanup remains in rose_remove_neigh() because free operations can be called from timer itself. This patch introduce rose_neigh_put() to handle the freeing of rose_neigh structures and modify rose_remove_neigh() to handle removal only. Signed-off-by: Takamitsu Iwai <takamitz@amazon.co.jp> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250823085857.47674-2-takamitz@amazon.co.jp Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-27pinctrl: Add pinctrl_pm_select_init_state helper functionChristian Bruel
If a platform requires an initial pinctrl state during probing, this helper function provides the client with access to the same initial state. eg: xxx_suspend_noirq ... pinctrl_pm_select_sleep_state xxx resume_noirq pinctrl_pm_select_init_state ... pinctrl_pm_select_default_state Signed-off-by: Christian Bruel <christian.bruel@foss.st.com> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://patch.msgid.link/20250820075411.1178729-3-christian.bruel@foss.st.com
2025-08-27mm: remove BDI_CAP_WRITEBACK_ACCTJoanne Koong
There are no users of BDI_CAP_WRITEBACK_ACCT now that fuse doesn't do its own writeback accounting. This commit removes BDI_CAP_WRITEBACK_ACCT. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Acked-by: David Hildenbrand <david@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2025-08-27fuse: use default writeback accountingJoanne Koong
commit 0c58a97f919c ("fuse: remove tmp folio for writebacks and internal rb tree") removed temp folios for dirty page writeback. Consequently, fuse can now use the default writeback accounting. With switching fuse to use default writeback accounting, there are some added benefits. This updates wb->writeback_inodes tracking as well now and updates writeback throughput estimates after writeback completion. This commit also removes inc_wb_stat() and dec_wb_stat(). These have no callers anymore now that fuse does not call them. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Bernd Schubert <bschubert@ddn.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2025-08-27sched/wait: Add wait_event_state_exclusive()Sergey Senozhatsky
Allows exclusive waits with a custom @state. Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2025-08-27fuse: add COPY_FILE_RANGE_64 that allows large copiesMiklos Szeredi
The FUSE protocol uses struct fuse_write_out to convey the return value of copy_file_range, which is restricted to uint32_t. But the COPY_FILE_RANGE interface supports a 64-bit size copies and there's no reason why copies should be limited to 32-bit. Introduce a new op COPY_FILE_RANGE_64, which is identical, except the number of bytes copied is returned in a 64-bit value. If the fuse server does not support COPY_FILE_RANGE_64, fall back to COPY_FILE_RANGE. Reported-by: Florian Weimer <fweimer@redhat.com> Closes: https://lore.kernel.org/all/lhuh5ynl8z5.fsf@oldenburg.str.redhat.com/ Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2025-08-27KVM: Allow and advertise support for host mmap() on guest_memfd filesFuad Tabba
Now that all the x86 and arm64 plumbing for mmap() on guest_memfd is in place, allow userspace to set GUEST_MEMFD_FLAG_MMAP and advertise support via a new capability, KVM_CAP_GUEST_MEMFD_MMAP. The availability of this capability is determined per architecture, and its enablement for a specific guest_memfd instance is controlled by the GUEST_MEMFD_FLAG_MMAP flag at creation time. Update the KVM API documentation to detail the KVM_CAP_GUEST_MEMFD_MMAP capability, the associated GUEST_MEMFD_FLAG_MMAP, and provide essential information regarding support for mmap in guest_memfd. Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shivank Garg <shivankg@amd.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250729225455.670324-22-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-27KVM: guest_memfd: Track guest_memfd mmap support in memslotFuad Tabba
Add a new internal flag, KVM_MEMSLOT_GMEM_ONLY, to the top half of memslot->flags (which makes it strictly for KVM's internal use). This flag tracks when a guest_memfd-backed memory slot supports host userspace mmap operations, which implies that all memory, not just private memory for CoCo VMs, is consumed through guest_memfd: "gmem only". This optimization avoids repeatedly checking the underlying guest_memfd file for mmap support, which would otherwise require taking and releasing a reference on the file for each check. By caching this information directly in the memslot, we reduce overhead and simplify the logic involved in handling guest_memfd-backed pages for host mappings. Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shivank Garg <shivankg@amd.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Acked-by: David Hildenbrand <david@redhat.com> Suggested-by: David Hildenbrand <david@redhat.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250729225455.670324-12-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-27KVM: guest_memfd: Add plumbing to host to map guest_memfd pagesFuad Tabba
Introduce the core infrastructure to enable host userspace to mmap() guest_memfd-backed memory. This is needed for several evolving KVM use cases: * Non-CoCo VM backing: Allows VMMs like Firecracker to run guests entirely backed by guest_memfd, even for non-CoCo VMs [1]. This provides a unified memory management model and simplifies guest memory handling. * Direct map removal for enhanced security: This is an important step for direct map removal of guest memory [2]. By allowing host userspace to fault in guest_memfd pages directly, we can avoid maintaining host kernel direct maps of guest memory. This provides additional hardening against Spectre-like transient execution attacks by removing a potential attack surface within the kernel. * Future guest_memfd features: This also lays the groundwork for future enhancements to guest_memfd, such as supporting huge pages and enabling in-place sharing of guest memory with the host for CoCo platforms that permit it [3]. Enable the basic mmap and fault handling logic within guest_memfd, but hold off on allow userspace to actually do mmap() until the architecture support is also in place. [1] https://github.com/firecracker-microvm/firecracker/tree/feature/secret-hiding [2] https://lore.kernel.org/linux-mm/cc1bb8e9bc3e1ab637700a4d3defeec95b55060a.camel@amazon.com [3] https://lore.kernel.org/all/c1c9591d-218a-495c-957b-ba356c8f8e09@redhat.com/T/#u Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shivank Garg <shivankg@amd.com> Acked-by: David Hildenbrand <david@redhat.com> Co-developed-by: Ackerley Tng <ackerleytng@google.com> Signed-off-by: Ackerley Tng <ackerleytng@google.com> Signed-off-by: Fuad Tabba <tabba@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250729225455.670324-11-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-27KVM: x86: Enable KVM_GUEST_MEMFD for all 64-bit buildsFuad Tabba
Enable KVM_GUEST_MEMFD for all KVM x86 64-bit builds, i.e. for "default" VM types when running on 64-bit KVM. This will allow using guest_memfd to back non-private memory for all VM shapes, by supporting mmap() on guest_memfd. Opportunistically clean up various conditionals that become tautologies once x86 selects KVM_GUEST_MEMFD more broadly. Specifically, because SW protected VMs, SEV, and TDX are all 64-bit only, private memory no longer needs to take explicit dependencies on KVM_GUEST_MEMFD, because it is effectively a prerequisite. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Fuad Tabba <tabba@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250729225455.670324-10-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-27KVM: Fix comment that refers to kvm uapi header pathFuad Tabba
The comment that points to the path where the user-visible memslot flags are refers to an outdated path and has a typo. Update the comment to refer to the correct path. Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shivank Garg <shivankg@amd.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250729225455.670324-9-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-27KVM: Fix comments that refer to slots_lockFuad Tabba
Fix comments so that they refer to slots_lock instead of slots_locks (remove trailing s). Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shivank Garg <shivankg@amd.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250729225455.670324-8-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-27KVM: Rename kvm_slot_can_be_private() to kvm_slot_has_gmem()Fuad Tabba
Rename kvm_slot_can_be_private() to kvm_slot_has_gmem() to improve clarity and accurately reflect its purpose. The function kvm_slot_can_be_private() was previously used to check if a given kvm_memory_slot is backed by guest_memfd. However, its name implied that the memory in such a slot was exclusively "private". As guest_memfd support expands to include non-private memory (e.g., shared host mappings), it's important to remove this association. The new name, kvm_slot_has_gmem(), states that the slot is backed by guest_memfd without making assumptions about the memory's privacy attributes. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shivank Garg <shivankg@amd.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Co-developed-by: David Hildenbrand <david@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250729225455.670324-7-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-27KVM: Rename CONFIG_KVM_GENERIC_PRIVATE_MEM to CONFIG_HAVE_KVM_ARCH_GMEM_POPULATEFuad Tabba
The original name was vague regarding its functionality. This Kconfig option specifically enables and gates the kvm_gmem_populate() function, which is responsible for populating a GPA range with guest data. The new name, HAVE_KVM_ARCH_GMEM_POPULATE, describes the purpose of the option: to enable arch-specific guest_memfd population mechanisms. It also follows the same pattern as the other HAVE_KVM_ARCH_* configuration options. This improves clarity for developers and ensures the name accurately reflects the functionality it controls, especially as guest_memfd support expands beyond purely "private" memory scenarios. Temporarily keep KVM_GENERIC_PRIVATE_MEM as an x86-only config so as to minimize churn, and to hopefully make it easier to see what features require HAVE_KVM_ARCH_GMEM_POPULATE. On that note, omit GMEM_POPULATE for KVM_X86_SW_PROTECTED_VM, as regular ol' memset() suffices for software-protected VMs. As for KVM_GENERIC_PRIVATE_MEM, a future change will select KVM_GUEST_MEMFD for all 64-bit KVM builds, at which point the intermediate config will become obsolete and can/will be dropped. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shivank Garg <shivankg@amd.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Co-developed-by: David Hildenbrand <david@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Fuad Tabba <tabba@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250729225455.670324-6-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-27KVM: Rename CONFIG_KVM_PRIVATE_MEM to CONFIG_KVM_GUEST_MEMFDFuad Tabba
Rename the Kconfig option CONFIG_KVM_PRIVATE_MEM to CONFIG_KVM_GUEST_MEMFD. The original name implied that the feature only supported "private" memory. However, CONFIG_KVM_PRIVATE_MEM enables guest_memfd in general, which is not exclusively for private memory. Subsequent patches in this series will add guest_memfd support for non-CoCo VMs, whose memory is not private. Renaming the Kconfig option to CONFIG_KVM_GUEST_MEMFD more accurately reflects its broader scope as the main Kconfig option for all guest_memfd-backed memory. This provides clearer semantics for the option and avoids confusion as new features are introduced. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shivank Garg <shivankg@amd.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Co-developed-by: David Hildenbrand <david@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20250729225455.670324-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-08-26kunit: Enable direct registration of parameter arrays to a KUnit testMarie Zhussupova
KUnit parameterized tests currently support two primary methods f or getting parameters: 1. Defining custom logic within a generate_params() function. 2. Using the KUNIT_ARRAY_PARAM() and KUNIT_ARRAY_PARAM_DESC() macros with a pre-defined static array and passing the created *_gen_params() to KUNIT_CASE_PARAM(). These methods present limitations when dealing with dynamically generated parameter arrays, or in scenarios where populating parameters sequentially via generate_params() is inefficient or overly complex. This patch addresses these limitations by adding a new `params_array` field to `struct kunit`, of the type `kunit_params`. The `struct kunit_params` is designed to store the parameter array itself, along with essential metadata including the parameter count, parameter size, and a get_description() function for providing custom descriptions for individual parameters. The `params_array` field can be populated by calling the new kunit_register_params_array() macro from within a param_init() function. This will register the array as part of the parameterized test context. The user will then need to pass kunit_array_gen_params() to the KUNIT_CASE_PARAM_WITH_INIT() macro as the generator function, if not providing their own. kunit_array_gen_params() is a KUnit helper that will use the registered array to generate parameters. The arrays passed to KUNIT_ARRAY_PARAM(,DESC) will also be registered to the parameterized test context for consistency as well as for higher availability of the parameter count that will be used for outputting a KTAP test plan for a parameterized test. This modification provides greater flexibility to the KUnit framework, allowing testers to easily register and utilize both dynamic and static parameter arrays. Link: https://lore.kernel.org/r/20250826091341.1427123-5-davidgow@google.com Reviewed-by: David Gow <davidgow@google.com> Reviewed-by: Rae Moar <rmoar@google.com> Signed-off-by: Marie Zhussupova <marievic@google.com> [Only output the test plan if using kunit_array_gen_params --David] Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-08-26kunit: Pass parameterized test context to generate_params()Marie Zhussupova
To enable more complex parameterized testing scenarios, the generate_params() function needs additional context beyond just the previously generated parameter. This patch modifies the generate_params() function signature to include an extra `struct kunit *test` argument, giving test users access to the parameterized test context when generating parameters. The `struct kunit *test` argument was added as the first parameter to the function signature as it aligns with the convention of other KUnit functions that accept `struct kunit *test` first. This also mirrors the "this" or "self" reference found in object-oriented programming languages. This patch also modifies xe_pci_live_device_gen_param() in xe_pci.c and nthreads_gen_params() in kcsan_test.c to reflect this signature change. Link: https://lore.kernel.org/r/20250826091341.1427123-4-davidgow@google.com Reviewed-by: David Gow <davidgow@google.com> Reviewed-by: Rae Moar <rmoar@google.com> Acked-by: Marco Elver <elver@google.com> Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Signed-off-by: Marie Zhussupova <marievic@google.com> [Catch some additional gen_params signatures in drm/xe/tests --David] Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-08-26kunit: Introduce param_init/exit for parameterized test context managementMarie Zhussupova
Add (*param_init) and (*param_exit) function pointers to `struct kunit_case`. Users will be able to set them via the new KUNIT_CASE_PARAM_WITH_INIT() macro. param_init/exit will be invoked by kunit_run_tests() once before and once after the parameterized test, respectively. They will receive the `struct kunit` that holds the parameterized test context; facilitating init and exit for shared state. This patch also sets param_init/exit to None in rust/kernel/kunit.rs. Link: https://lore.kernel.org/r/20250826091341.1427123-3-davidgow@google.com Reviewed-by: Rae Moar <rmoar@google.com> Reviewed-by: David Gow <davidgow@google.com> Signed-off-by: Marie Zhussupova <marievic@google.com> Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-08-26kunit: Add parent kunit for parameterized test contextMarie Zhussupova
Currently, KUnit parameterized tests lack a mechanism to share resources across parameter runs because the same `struct kunit` instance is cleaned up and reused for each run. This patch introduces parameterized test context, enabling test users to share resources between parameter runs. It also allows setting up resources that need to be available for all parameter runs only once, which is helpful in cases where setup is expensive. To establish a parameterized test context, this patch adds a parent pointer field to `struct kunit`. This allows resources added to the parent `struct kunit` to be shared and accessible across all parameter runs. In kunit_run_tests(), the default `struct kunit` created is now designated to act as the parameterized test context whenever a test is parameterized. Subsequently, a new `struct kunit` is made for each parameter run, and its parent pointer is set to the `struct kunit` that holds the parameterized test context. Link: https://lore.kernel.org/r/20250826091341.1427123-2-davidgow@google.com Reviewed-by: David Gow <davidgow@google.com> Reviewed-by: Rae Moar <rmoar@google.com> Signed-off-by: Marie Zhussupova <marievic@google.com> Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-08-26ipv6: sr: Prepare HMAC key ahead of timeEric Biggers
Prepare the HMAC key when it is added to the kernel, instead of preparing it implicitly for every packet. This significantly improves the performance of seg6_hmac_compute(). A microbenchmark on x86_64 shows seg6_hmac_compute() (with HMAC-SHA256) dropping from ~1978 cycles to ~1419 cycles, a 28% improvement. The size of 'struct seg6_hmac_info' increases by 128 bytes, but that should be fine, since there should not be a massive number of keys. Signed-off-by: Eric Biggers <ebiggers@kernel.org> Link: https://patch.msgid.link/20250824013644.71928-3-ebiggers@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-26ipv6: sr: Use HMAC-SHA1 and HMAC-SHA256 library functionsEric Biggers
Use the HMAC-SHA1 and HMAC-SHA256 library functions instead of crypto_shash. This is simpler and faster. Pre-allocating per-CPU hash transformation objects and descriptors is no longer needed, and a microbenchmark on x86_64 shows seg6_hmac_compute() (with HMAC-SHA256) dropping from ~2494 cycles to ~1978 cycles, a 20% improvement. Signed-off-by: Eric Biggers <ebiggers@kernel.org> Link: https://patch.msgid.link/20250824013644.71928-2-ebiggers@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-26ipv4: Convert ->flowi4_tos to dscp_t.Guillaume Nault
Convert the ->flowic_tos field of struct flowi_common from __u8 to dscp_t, rename it ->flowic_dscp and propagate these changes to struct flowi and struct flowi4. We've had several bugs in the past where ECN bits could interfere with IPv4 routing, because these bits were not properly cleared when setting ->flowi4_tos. These bugs should be fixed now and the dscp_t type has been introduced to ensure that variables carrying DSCP values don't accidentally have any ECN bits set. Several variables and structure fields have been converted to dscp_t already, but the main IPv4 routing structure, struct flowi4, is still using a __u8. To avoid any future regression, this patch converts it to dscp_t. There are many users to convert at once. Fortunately, around half of ->flowi4_tos users already have a dscp_t value at hand, which they currently convert to __u8 using inet_dscp_to_dsfield(). For all of these users, we just need to drop that conversion. But, although we try to do the __u8 <-> dscp_t conversions at the boundaries of the network or of user space, some places still store TOS/DSCP variables as __u8 in core networking code. Those can hardly be converted either because the data structure is part of UAPI or because the same variable or field is also used for handling ECN in other parts of the code. In all of these cases where we don't have a dscp_t variable at hand, we need to use inet_dsfield_to_dscp() when interacting with ->flowi4_dscp. Changes since v1: * Fix space alignment in __bpf_redirect_neigh_v4() (Ido). Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/29acecb45e911d17446b9a3dbdb1ab7b821ea371.1756128932.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-26devlink: Make health reporter burst period configurableShahar Shitrit
Enable configuration of the burst period — a time window starting from the first error recovery, during which the reporter allows recovery attempts for each reported error. This feature is helpful when a single underlying issue causes multiple errors, as it delays the start of the grace period to allow sufficient time for recovering all related errors. For example, if multiple TX queues time out simultaneously, a sufficient burst period could allow all affected TX queues to be recovered within that window. Without this period, only the first TX queue that reports a timeout will undergo recovery, while the remaining TX queues will be blocked once the grace period begins. Configuration example: $ devlink health set pci/0000:00:09.0 reporter tx burst_period 500 Configuration example with ynl: ./tools/net/ynl/pyynl/cli.py \ --spec Documentation/netlink/specs/devlink.yaml \ --do health-reporter-set --json '{ "bus-name": "auxiliary", "dev-name": "mlx5_core.eth.0", "port-index": 65535, "health-reporter-name": "tx", "health-reporter-burst-period": 500 }' Signed-off-by: Shahar Shitrit <shshitrit@nvidia.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com> Reviewed-by: Carolina Jubran <cjubran@nvidia.com> Signed-off-by: Mark Bloch <mbloch@nvidia.com> Link: https://patch.msgid.link/20250824084354.533182-5-mbloch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-26devlink: Introduce burst period for health reporterShahar Shitrit
Currently, the devlink health reporter starts the grace period immediately after handling an error, blocking any further recoveries until it finished. However, when a single root cause triggers multiple errors in a short time frame, it is desirable to treat them as a bulk of errors and to allow their recoveries, avoiding premature blocking of subsequent related errors, and reducing the risk of inconsistent or incomplete error handling. To address this, introduce a configurable burst period for devlink health reporter. Start this period when the first error is handled, and allow recovery attempts for reported errors during this window. Once burst period expires, begin the grace period to block further recoveries until it concludes. Timeline summary: ----|--------|------------------------------/----------------------/-- error is error is burst period grace period reported recovered (recoveries allowed) (recoveries blocked) For calculating the burst period duration, use the same last_recovery_ts as the grace period. Update it on recovery only when the burst period is inactive (either disabled or at the first error). This patch implements the framework for the burst period and effectively sets its value to 0 at reporter creation, so the current behavior remains unchanged, which ensures backward compatibility. A downstream patch will make the burst period configurable. Signed-off-by: Shahar Shitrit <shshitrit@nvidia.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Mark Bloch <mbloch@nvidia.com> Link: https://patch.msgid.link/20250824084354.533182-4-mbloch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-26devlink: Move graceful period parameter to reporter opsShahar Shitrit
Move the default graceful period from a parameter to devlink_health_reporter_create() to a field in the devlink_health_reporter_ops structure. This change improves consistency, as the graceful period is inherently tied to the reporter's behavior and recovery policy. It simplifies the signature of devlink_health_reporter_create() and its internal helper functions. It also centralizes the reporter configuration at the ops structure, preparing the groundwork for a downstream patch that will introduce a devlink health reporter burst period attribute whose default value will similarly be provided by the driver via the ops structure. Signed-off-by: Shahar Shitrit <shshitrit@nvidia.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Mark Bloch <mbloch@nvidia.com> Link: https://patch.msgid.link/20250824084354.533182-2-mbloch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-26net: phy: fixed: let fixed_phy_add always use addr 0 and remove return valueHeiner Kallweit
We have only two users of fixed_phy_add(), both use address 0 and ignore the return value. So simplify fixed_phy_add() accordingly. Whilst at it, constify the fixed_phy_status configs. Note: fixed_phy_add() is a legacy function which shouldn't be used in new code, as it's use may be problematic: - No check whether a fixed phy exists already at the given address - If fixed_phy_register() is called afterwards by any other driver, then it will also use phy_addr 0, because fixed_phy_add() ignores the ida which manages address assignment Drivers using a fixed phy created by fixed_phy_add() in platform code, should dynamically create a fixed phy with fixed_phy_register() instead. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Link: https://patch.msgid.link/762700e5-a0b1-41af-aa03-929822a39475@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-26net: phy: introduce phy_id_compare_vendor() PHY ID helperChristian Marangi
Introduce phy_id_compare_vendor() PHY ID helper to compare a PHY ID with the PHY ID Vendor using the generic PHY ID Vendor mask. While at it also rework the PHY_ID_MATCH macro and move the mask to dedicated define so that PHY driver can make use of the mask if needed. Signed-off-by: Christian Marangi <ansuelsmth@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Link: https://patch.msgid.link/20250823134431.4854-1-ansuelsmth@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-26lib/crypto: md5: Add MD5 and HMAC-MD5 library functionsEric Biggers
Add library functions for MD5, including HMAC support. The MD5 implementation is derived from crypto/md5.c. This closely mirrors the corresponding SHA-1 and SHA-2 changes. Like SHA-1 and SHA-2, support for architecture-optimized MD5 implementations is included. I originally proposed dropping those, but unfortunately there is an AF_ALG user of the PowerPC MD5 code (https://lore.kernel.org/r/c4191597-341d-4fd7-bc3d-13daf7666c41@csgroup.eu/), and dropping that code would be viewed as a performance regression. We don't add new software algorithm implementations purely for AF_ALG, as escalating to kernel mode merely to do calculations that could be done in userspace is inefficient and is completely the wrong design. But since this one already existed, it gets grandfathered in for now. An objection was also raised to dropping the SPARC64 MD5 code because it utilizes the CPU's direct support for MD5, although it remains unclear that anyone is using that. Regardless, we'll keep these around for now. Note that while MD5 is a legacy algorithm that is vulnerable to practical collision attacks, it still has various in-kernel users that implement legacy protocols. Switching to a simple library API, which is the way the code should have been organized originally, will greatly simplify their code. For example: MD5: drivers/md/dm-crypt.c (for lmk IV generation) fs/nfsd/nfs4recover.c fs/ecryptfs/ fs/smb/client/ net/{ipv4,ipv6}/ (for TCP-MD5 signatures) HMAC-MD5: fs/smb/client/ fs/smb/server/ (Also net/sctp/ if it continues using HMAC-MD5 for cookie generation. However, that use case has the flexibility to upgrade to a more modern algorithm, which I'll be proposing instead.) As usual, the "md5" and "hmac(md5)" crypto_shash algorithms will also be reimplemented on top of these library functions. For "hmac(md5)" this will provide a faster, more streamlined implementation. Link: https://lore.kernel.org/r/20250805222855.10362-2-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-08-26drm: Add a vendor-specific recovery method to drm device wedged ueventRiana Tauro
Address the need for a recovery method (firmware flash on Firmware errors) introduced in the later patches of Xe KMD. Whenever XE KMD detects a firmware error, a firmware flash is required to recover the device to normal operation. The initial proposal to use 'firmware-flash' as a recovery method was not applicable to other drivers and could cause multiple recovery methods specific to vendors to be added. To address this a more generic 'vendor-specific' method is introduced, guiding users to refer to vendor specific documentation and system logs for detailed vendor specific recovery procedure. Add a recovery method 'WEDGED=vendor-specific' for such errors. Vendors must provide additional recovery documentation if this method is used. It is the responsibility of the consumer to refer to the correct vendor specific documentation and usecase before attempting a recovery. For example: If driver is XE KMD, the consumer must refer to the documentation of 'Device Wedging' under 'Documentation/gpu/xe/'. v2: fix documentation (Raag) v3: add more details to commit message (Sima, Rodrigo, Raag) add an example script to the documentation (Raag) v4: use consistent naming (Raag) v5: fix commit message v6: add more documentation Cc: André Almeida <andrealmeid@igalia.com> Cc: Christian König <christian.koenig@amd.com> Cc: David Airlie <airlied@gmail.com> Cc: Simona Vetter <simona.vetter@ffwll.ch> Cc: Maxime Ripard <mripard@kernel.org> Signed-off-by: Riana Tauro <riana.tauro@intel.com> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Acked-by: Maxime Ripard <mripard@kernel.org> Link: https://lore.kernel.org/r/20250826063419.3022216-3-riana.tauro@intel.com Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
2025-08-26drm/vesadrm: Support DRM_FORMAT_C8Thomas Zimmermann
Add support for DRM_FORMAT_C8 to vesadrm. The new pixel-format description PIXEL_FORMAT_C8 describes the layout. Vesadrm's helpers vesadrm_fill_palette_lut() and vesadrm_load_palette_lut() set the hardware palette according to the CRTC's output format. The driver emulates XRGB8888 by converting the source buffer to RGB332 and using the resulting 256 colors as index into the hardware palette. The hardware palette converts back to RGB during scanout. This has no overhead compared to other format conversion, but allows common userspace, such as Wayland compositors, to operate on the display. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://lore.kernel.org/r/20250714151513.309475-10-tzimmermann@suse.de
2025-08-26drm/color-mgmt: Prepare for RGB332 palettesThomas Zimmermann
Add helper drm_crtc_fill_palette_332(), which fills palettes with RGB332 color data. Each color in RGB332 format serves as an index into an 8-bit palette that stores the corresponding component-based colors. Vesadrm will use the new helper to emulate RGB formats on top of framebuffers in C8 format. v2: - add comments on bit operations (Javier) Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://lore.kernel.org/r/20250714151513.309475-6-tzimmermann@suse.de
2025-08-26video: screen_info: Add pixel-format helper for linear framebuffersThomas Zimmermann
Add screen_info_pixel_format(), which converts a screen_info's information about the color format to struct pixel_format. The encoding within the screen_info structure is complex and therefore prone to errors. Later patches will convert callers to use the pixel format. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://lore.kernel.org/r/20250714151513.309475-3-tzimmermann@suse.de
2025-08-26video: pixel_format: Add compare helpersThomas Zimmermann
Add helpers that compare two pixel-format descriptions against each other. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://lore.kernel.org/r/20250714151513.309475-2-tzimmermann@suse.de
2025-08-26perf: Remove get_perf_callchain() init_nr argumentJosh Poimboeuf
The 'init_nr' argument has double duty: it's used to initialize both the number of contexts and the number of stack entries. That's confusing and the callers always pass zero anyway. Hard code the zero. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Namhyung Kim <Namhyung@kernel.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20250820180428.259565081@kernel.org
2025-08-26memblock: fix kernel-doc for MEMBLOCK_RSRV_NOINITMike Rapoport (Microsoft)
The kernel-doc description of MEMBLOCK_RSRV_NOINIT and memblock_reserved_mark_noinit() do not accurately describe their functionality. Expand their kernel doc to make it clear that the user of MEMBLOCK_RSRV_NOINIT is responsible to properly initialize the struct pages for such regions and add more details about effects of using this flag. Reviewed-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/f8140a17-c4ec-489b-b314-d45abe48bf36@redhat.com Link: https://lore.kernel.org/r/20250826071947.1949725-1-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
2025-08-26vhost: Fix ioctl # for VHOST_[GS]ET_FORK_FROM_OWNERNamhyung Kim
The VHOST_[GS]ET_FEATURES_ARRAY ioctl already took 0x83 and it would result in a build error when the vhost uapi header is used for perf tool build like below. In file included from trace/beauty/ioctl.c:93: tools/perf/trace/beauty/generated/ioctl/vhost_virtio_ioctl_array.c: In function ‘ioctl__scnprintf_vhost_virtio_cmd’: tools/perf/trace/beauty/generated/ioctl/vhost_virtio_ioctl_array.c:36:18: error: initialized field overwritten [-Werror=override-init] 36 | [0x83] = "SET_FORK_FROM_OWNER", | ^~~~~~~~~~~~~~~~~~~~~ tools/perf/trace/beauty/generated/ioctl/vhost_virtio_ioctl_array.c:36:18: note: (near initialization for ‘vhost_virtio_ioctl_cmds[131]’) Fixes: 7d9896e9f6d02d8a ("vhost: Reintroduce kthread API and add mode selection") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Message-Id: <20250819063958.833770-1-namhyung@kernel.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Tested-by: Lei Yang <leiyang@redhat.com>
2025-08-26Revert "virtio: reject shm region if length is zero"Igor Torrente
The commit 206cc44588f7 ("virtio: reject shm region if length is zero") breaks the Virtio-gpu `host_visible` feature. As you can see in the snippet below, host_visible_region is zero because of the `kzalloc`. It's using the `vm_get_shm_region` (drivers/virtio/virtio_mmio.c:536) to read the `addr` and `len` from qemu/crosvm. ``` drivers/gpu/drm/virtio/virtgpu_kms.c 132 vgdev = drmm_kzalloc(dev, sizeof(struct virtio_gpu_device), GFP_KERNEL); [...] 177 if (virtio_get_shm_region(vgdev->vdev, &vgdev->host_visible_region, 178 VIRTIO_GPU_SHM_ID_HOST_VISIBLE)) { ``` Now it always fails. To fix, revert the offending commit. Fixes: 206cc44588f7 ("virtio: reject shm region if length is zero") Signed-off-by: Igor Torrente <igor.torrente@collabora.com> Message-Id: <20250807124145.81816-1-igor.torrente@collabora.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>