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8 daysMerge tag 'net-7.2-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Lots of fixes, double the count even for the 'new normal'. Largely due to my time off followed by a networking conference which distracted most maintainers (less so the AI generators). Including fixes from Bluetooth and WiFi. Current release - regressions: - wifi: mt76: fix MAC address for non OF pcie cards Current release - new code bugs: - mptcp: fix BUILD_BUG_ON on legacy ARM config - wifi: cfg80211: guard optional PMSR nominal time Previous releases - regressions: - qrtr: ns: raise node count limit to 512, we arbitrarily picked 256 as a limit, turns out it was too low for real world deployments - vhost-net: fix TX stall when vhost owns virtio-net header - eth: amd-xgbe: fix MAC_AUTO_SW handling in CL37 AN - wifi: ath12k: fix low MLO RX throughput on WCN7850 Previous releases - always broken: - number of random AI fixes for SCTP, RDS and TIPC protocols - more AI-looking fixes for WiFi drivers - number of fixes for missing pointer reloading after skb pull - reject BPF redirect use from qdisc qevent block - tcp: initialize standalone TCP-AO response padding - vsock/virtio: collapse receive queue under memory pressure to avoid client OOMing the host with tiny messages - ipv4: icmp: fill flow parameters in icmp_route_lookup decoy lookup, make sure the ICMP response routing follows the routing policy - gro: fix double aggregation of flush-marked skbs - ovpn: fix various refcount bugs - tls: device: push pending open record on splice EOF - eth: mlx5: - use sender devcom for MPV master-up - fix MCIA register buffer overflow on 32 dword reads" * tag 'net-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (234 commits) drop_monitor: perform u64_stats updates under IRQ-disabled section drop_monitor: fix size calculations for 64-bit attributes net: drop_monitor: fix info leak in NET_DM_ATTR_PAYLOAD mptcp: fix BUILD_BUG_ON on legacy ARM config selftests: mptcp: userspace_pm: fix undefined variable port mptcp: fix stale skb->sk reference on subflow close mptcp: pm: userspace: fix use-after-free in get_local_id mptcp: decrement subflows counter on failed passive join mac802154: hold an interface reference across the scan worker sctp: don't free the ASCONF's own transport in DEL-IP processing phonet: check register_netdevice_notifier() error in phonet_device_init() phonet: pep: fix use-after-free in pep_get_sb() bnge/bng_re: fix ring ID widths tipc: fix integer overflow in tipc_recvmsg() and tipc_recvstream() net: airoha: fix ETS channel derivation in airoha_tc_setup_qdisc_ets() mctp: check register_netdevice_notifier() error in mctp_device_init() ptp: netc: explicitly clear TMR_OFF during initialization rds: tcp: unregister sysctl before tearing down listen socket ipv6: Change allocation flags to match rcu_read_lock section requirements net: slip: serialize receive against buffer reallocation ...
8 dayss390/ptff: Export ptff_function_mask[]Sven Schnelle
Export the ptff_function_mask to make ptff_query() usable in modules. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Link: https://patch.msgid.link/20260714130342.1971700-2-svens@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-15s390/perf_cpum_cf: Add missing array_index_nospec() to __hw_perf_event_init()Sumanth Korikkar
ev variable is userspace controlled via event->attr.config and used as an array index after bounds checking, but without speculation barriers. Add the missing array_index_nospec() call to prevent speculative execution. Cc: stable@vger.kernel.org Fixes: 212188a596d1 ("[S390] perf: add support for s390x CPU counters") Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-08s390: Add build salt to the vDSOBastian Blank
The vDSO needs to have a unique build id in a similar manner to the kernel and modules. Use the build salt macro. Signed-off-by: Bastian Blank <waldi@debian.org> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-08s390/diag: Add missing array_index_nospec() call to memtop_get_page_count()Heiko Carstens
'level' is user space controlled and used to read from an array. Add the missing array_index_nospec() call to prevent speculative execution. Cc: stable@vger.kernel.org Fixes: 0d30871739ab ("s390/diag: Add memory topology information via diag310") Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Mete Durlu <meted@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-06-18s390/idle: Add missing EXPORT_SYMBOL_GPL()Heiko Carstens
Uwe Kleine-König reported this build breakage caused by a recent commit which provides arch specific kcpustat_field_idle()/kcpustat_field_iowait() functions: ERROR: modpost: "arch_kcpustat_field_idle" [drivers/leds/trigger/ledtrig-activity.ko] undefined! ERROR: modpost: "arch_kcpustat_field_iowait" [drivers/leds/trigger/ledtrig-activity.ko] undefined! Fix this by adding the missing EXPORT_SYMBOL_GPL(). Fixes: 670e057744e0 ("s390/idle: Provide arch specific kcpustat_field_idle()/kcpustat_field_iowait()") Reported-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Closes: https://lore.kernel.org/r/ajKsG0JP6qTssQBX@monoceros Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Tested-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-16Merge branch 'idle-time-acc' into featuresAlexander Gordeev
Heiko Carstens says: =================== This is supposed to improve s390 idle time accounting, and brings it back to the state it was before arch_cpu_idle_time() was removed from s390 [3]. In result all cpu time accounting is done by the s390 architecture backend again, instead of having a mix of architecure specific and common code accounting (common code: idle, s390 architecture: everything else). =================== Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-16Merge tag 's390-7.2-1' of ↵Linus Torvalds
gitolite.kernel.org:pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Alexander Gordeev: - Use CIO device online variable instead of the internal FSM state to determine device availability during purge operations - Remove extra check of task_stack_page() because try_get_task_stack() already takes care of that when reading /proc/<pid>/wchan - Allow user-space to use the new SCLP action qualifier 4 for to provide NVMe SMART log data to the platform. - Send AP CHANGE uevents on successful bind and successful association to notify user-space about SE operations on AP queue devices - Add an s390dbf kernel parameter to configure debug log levels and area sizes during early boot - On arm64 the empty zero page is going to be mapped read-only. Do the same for s390 with an explicit set_memory_ro() call - Improve s390-specific bcr_serialize() and cpu_relax() implementations - Remove all unused variables to avoid allmodconfig W=1 build fails with latest clang-23 - Cleanup default Kconfig values for s390 selftests - Add a s390-tod trace clock to allow comparing trace timestamps between different systems or virtual machines on s390 - Remove the s390 implementation of strlcat() in favor of the generic variant - Make consistent the calling order between page_table_check_pte_clear() and secure page conversion across all code paths - Rearrange some fields within AP and zcrypt structs to reduce memory consumption and unused holes - Shorten GR_NUM and VX_NUM macros and move them to a separate header - Replace __get_free_page() with kmalloc() in few sources - Introduce an infrastructure for more efficient this_cpu operations. Eliminate conditional branches when PREEMPT_NONE is removed - Enable Rust support - Use z10 as minimum architecture level, similar to the boot code, to enforce a defined architecture level set - Improve and convert various mem*() helper functions to C. For that add .noinstr.text section to avoid orphaned warnings from the linker - Fix the function pointer type in __ret_from_fork() to correct the indirect call to match kernel thread return type of int - Revert support for DCACHE_WORD_ACCESS to avoid an endless exception loop on read from donated Ultravisor pages at unaligned addresses * tag 's390-7.2-1' of gitolite.kernel.org:pub/scm/linux/kernel/git/s390/linux: (52 commits) s390: Revert support for DCACHE_WORD_ACCESS s390/process: Fix kernel thread function pointer type s390/tishift: Convert __ashlti3(), __ashrti3(), __lshrti3() to C s390/memmove: Optimize backward copy case s390/string: Convert memset(16|32|64)() to C s390/string: Convert memcpy() to C s390/string: Convert memset() to C s390/string: Convert memmove() to C s390/string: Add -ffreestanding compile option to string.o s390: Add .noinstr.text to boot and purgatory linker scripts s390/purgatory: Enforce z10 minimum architecture level s390: Enable Rust support s390/cmpxchg: Fix KASAN stack-out-of-bounds in atomic helpers rust: helpers: Add memchr wrapper for string operations rust/bindgen_parameters: Mark s390 types as opaque to prevent repr conflicts s390/jump_label: Implement ARCH_STATIC_BRANCH_JUMP_ASM and ARCH_STATIC_BRANCH_ASM macros s390/bug: Provide ARCH_WARN_ASM for Rust WARN/BUG support s390/ap: Fix locking issue in SE bind and associate sysfs functions s390/percpu: Provide arch_this_cpu_write() implementation s390/percpu: Provide arch_this_cpu_read() implementation ...
2026-06-15s390/idle: Remove idle time and count sysfs filesHeiko Carstens
Remove the s390 specific idle_time_us and idle_count per cpu sysfs files. They do not provide any additional value. The risk that there are existing applications which rely on these architecture specific files should be very low. However if it turns out such applications exist, this can be easily reverted. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-15s390/idle: Provide arch specific kcpustat_field_idle()/kcpustat_field_iowait()Heiko Carstens
The former s390 specific arch_cpu_idle_time() implementation was removed, since its implementation was racy and reported idle time could go backwards [1]. However this removal was not necessary, since independently of the s390 architecture specific races there exists the iowait counter update race, which can also lead to reported idle time going backwards [2]. With Frederic Weisbecker's recent cpu idle time accounting refactoring kernel_cpustat got a sequence counter. Use this to implement s390 specific variants of kcpustat_field_idle() and kcpustat_field_iowait(). This is logically a revert of [1] and moves cpu idle time accounting back into s390 architecture code, which is also more precise than the dyntick idle time accounting by nohz/scheduler. For comparing cross cpu time stamps it is necessary to use the stcke instead of the stckf instruction in irq entry path. Furthermore this open-codes a sequence lock in assembler and C code, which is required to update the irq entry time stamp to the per cpu idle_data structure in a race free manner. [1] commit be76ea614460 ("s390/idle: remove arch_cpu_idle_time() and corresponding code") [2] commit ead70b752373 ("timers/nohz: Add a comment about broken iowait counter update race") Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-15s390/irq/idle: Use stcke instead of stckf for time stampsHeiko Carstens
The upcoming cpu idle time accounting rework involves comparing and subtracting cross cpu time stamps. Time stamps created with the stckf instruction monotonic with respect to the local cpu. For cross cpu monotonic time stamps the slightly slower stcke instruction has to be used [1]. Convert the idle time accounting relevant usages of stckf to stcke. [1] Principles of Operation - Setting and Inspecting the Clock Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-11s390/process: Fix kernel thread function pointer typeHeiko Carstens
In case of a kernel thread __ret_from_fork() calls the specified function indirectly. Fix the kernel thread function pointer, since kernel threads return an int instead of void. Fixes: 56e62a737028 ("s390: convert to generic entry") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-03s390/percpu: Infrastructure for more efficient this_cpu operationsHeiko Carstens
With the intended removal of PREEMPT_NONE this_cpu operations based on atomic instructions, guarded with preempt_disable()/preempt_enable() pairs become more expensive: the preempt_disable() / preempt_enable() pairs are not optimized away anymore during compile time. In particular the conditional call to preempt_schedule_notrace() after preempt_enable() adds additional code and register pressure. E.g. this simple C code sequence DEFINE_PER_CPU(long, foo); long bar(long a) { return this_cpu_add_return(foo, a); } generates this code: 11a976: eb af f0 68 00 24 stmg %r10,%r15,104(%r15) 11a97c: b9 04 00 ef lgr %r14,%r15 11a980: b9 04 00 b2 lgr %r11,%r2 11a984: e3 f0 ff c8 ff 71 lay %r15,-56(%r15) 11a98a: e3 e0 f0 98 00 24 stg %r14,152(%r15) 11a990: eb 01 03 a8 00 6a asi 936,1 <- __preempt_count_add(1) 11a996: c0 10 00 d2 ac b5 larl %r1,1b70300 <- address of percpu var 11a9a0: e3 10 23 b8 00 08 ag %r1,952 <- add percpu offset 11a9a6: eb ab 10 00 00 e8 laag %r10,%r11,0(%r1) <- atomic op 11a9ac: eb ff 03 a8 00 6e alsi 936,-1 <- __preempt_count_dec_and_test() 11a9b2: a7 54 00 05 jnhe 11a9bc <bar+0x4c> 11a9b6: c0 e5 00 76 d1 bd brasl %r14,ff4d30 <preempt_schedule_notrace> 11a9bc: b9 e8 b0 2a agrk %r2,%r10,%r11 11a9c0: eb af f0 a0 00 04 lmg %r10,%r15,160(%r15) 11a9c6 07 fe br %r14 Even though the above example is more or less the worst case, since the branch to preempt_schedule_notrace() requires a stackframe, which otherwise wouldn't be necessary, there is also the conditional jnhe branch instruction. Get rid of the conditional branch with the following code sequence: 11a8e6: c0 30 00 d0 c5 0d larl %r3,1b33300 11a8ec: b9 04 00 43 lgr %r4,%r3 11a8f0: eb 00 43 c0 00 52 mviy 960,4 11a8f6: e3 40 03 b8 00 08 ag %r4,952 11a8fc: eb 52 40 00 00 e8 laag %r5,%r2,0(%r4) 11a902: eb 00 03 c0 00 52 mviy 960,0 11a908: b9 08 00 25 agr %r2,%r5 11a90c 07 fe br %r14 The general idea is that this_cpu operations based on atomic instructions are guarded with mviy instructions: - The first mviy instruction writes the register number, which contains the percpu address variable to lowcore. This also indicates that a percpu code section is executed. - The first instruction following the mviy instruction must be the ag instruction which adds the percpu offset to the percpu address register. - Afterwards the atomic percpu operation follows. - Then a second mviy instruction writes a zero to lowcore, which indicates the end of the percpu code section. - In case of an interrupt/exception/nmi the register number which was written to lowcore is copied to the exception frame (pt_regs), and a zero is written to lowcore. - On return to the previous context it is checked if a percpu code section was executed (saved register number not zero), and if the process was migrated to a different cpu. If the percpu offset was already added to the percpu address register (instruction address does _not_ point to the ag instruction) the content of the percpu address register is adjusted so it points to percpu variable of the new cpu. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-02s390/time: Prepare to stop elapsing in dynticks-idleFrederic Weisbecker
Currently the tick subsystem stores the idle cputime accounting in private fields, allowing cohabitation with architecture idle vtime accounting. The former is fetched on online CPUs, the latter on offline CPUs. For consolidation purposes, architecture vtime accounting will continue to account the cputime but will make a break when the idle tick is stopped. The dyntick cputime accounting will then be relayed by the tick subsystem so that the idle cputime is still seen advancing coherently even when the tick isn't there to flush the idle vtime. Prepare for that and introduce three new APIs which will be used in subsequent patches: - vtime_dynticks_start() is deemed to be called when idle enters in dyntick mode. The idle cputime that elapsed so far is accumulated and accounted. Also idle time accounting is ignored. - vtime_dynticks_stop() is deemed to be called when idle exits from dyntick mode. The vtime entry clocks are fast-forward to current time so that idle accounting restarts elapsing from now. Also idle time accounting is resumed. - vtime_reset() is deemed to be called from dynticks idle IRQ entry to fast-forward the clock to current time so that the IRQ time is still accounted by vtime while nohz cputime is paused. Also accumulated vtime won't be flushed from dyntick-idle ticks to avoid accounting twice the idle cputime, along with nohz accounting. Co-developed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Tested-by: Shrikanth Hegde <sshegde@linux.ibm.com> Link: https://patch.msgid.link/20260508131647.43868-7-frederic@kernel.org
2026-05-26s390/tracing: Add s390-tod clockSven Schnelle
In order to allow comparing trace timestamps between different systems or virtual machines on s390, add a s390-tod trace clock. This clock just uses the returned TOD clock value from stcke directly. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-26s390/debug: Remove s390dbf_sysctl_header variableHeiko Carstens
allmodconfig with clang W=1 points out an unused global variable: arch/s390/kernel/debug.c:1237:33: error: variable 's390dbf_sysctl_header' set but not used [-Werror,-Wunused-but-set-global] Just remove the variable. There is no point in adding error handling for a failing register_sysctl() call. Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-20s390/topology: Use zero-based numbering for containing entitiesAlexandra Winter
Start the numbering scheme for higher-level topology structures (like socket, book, drawer) at zero, matching the convention for other hardware identifiers like e.g. CPU numbers. Hardware documentation, the Hardware Management Console and other tools like zmemtopo also use zero-based numbering for these containing entities. Aligning the numbering in sysfs, procfs, and tools like lscpu improves user experience by making it easier to correlate topology information across different interfaces. If available, Linux on s390 derives this physical topology information from the stsi function code 15 store_topology instruction, which is defined to start at 1 for the lowest numbered container id. Subtract one, so drawer_id, book_id and socket_id in cpu_topology[] start with 0 for the lowest numbered entity; and /proc/cpuinfo and tools like 'lscpu -ye' display the expected values. Display only, no functional change intended. Example: In a partition with 3 cores in a system with 8 cores per socket; 2 sockets per book; 4 books per dawer; and 4 drawers: Before this fix: $ lscpu -ye CPU NODE DRAWER BOOK SOCKET CORE L1d:L1i:L2 ONLINE CONFIGURED POLARIZATION ADDRESS 0 0 2 4 1 0 0:0:0 yes yes vert-high 0 1 0 2 4 1 0 1:1:1 yes yes vert-high 1 2 0 2 4 1 1 2:2:2 yes yes vert-medium 2 3 0 2 4 1 1 3:3:3 yes yes vert-medium 3 4 0 2 4 2 3 4:4:4 yes yes vert-low 4 5 0 2 4 2 3 5:5:5 yes yes vert-low 5 After this fix: $ lscpu -ye CPU NODE DRAWER BOOK SOCKET CORE L1d:L1i:L2 ONLINE CONFIGURED POLARIZATION ADDRESS 0 0 1 3 0 0 0:0:0 yes yes vert-high 0 1 0 1 3 0 0 1:1:1 yes yes vert-high 1 2 0 1 3 0 1 2:2:2 yes yes vert-medium 2 3 0 1 3 0 1 3:3:3 yes yes vert-medium 3 4 0 1 3 1 3 4:4:4 yes yes vert-low 4 5 0 1 3 1 3 5:5:5 yes yes vert-low 5 For KVM guests, qemu emulates the stsi FC15 store_topology instruction. This emulation currently erroneously starts id numbering at 0. A qemu fix is proposed that makes this emulation compliant to the stsi architecture. In case a guest with this patch is running on a qemu without the other fix, it can happen that ids of 255 are displayed erroneously. z/VM currently does not provide or emulate physical topology information to its guests. So this patch does not change anything for z/VM guests. Fixes: 10d385895055 ("[S390] topology: expose core identifier") Signed-off-by: Alexandra Winter <wintera@linux.ibm.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com> Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-11s390/debug: Add s390dbf kernel parameterPeter Oberparleiter
Problem determination using s390dbf logging sometimes requires changing the default logging level or log area size. While this is possible using sysfs interfaces, there is no easy way to adjust these parameters for early boot code that emits logs before userspace is available. Add an s390dbf kernel parameter to address this shortcoming. The parameter can be used to specify log level and area size (in units of pages). A level of '-' turns logging off for an area. Logs can be identified by name or a shell-style pattern. Parameter format: s390dbf=<name|pattern>:[<level>|-]:[<pages>][,...] Example: s390dbf=cio*:6:128,sclp_err::2 Specified parameters are applied immediately during debug area registration for regular log areas. For early, static debug areas, log levels are changed during early_param() parsing, while size changes are applied at arch_initcall-time. Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com> Tested-by: Vineeth Vijayan <vneethv@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-11s390/pai: Fix missing PAI counter increments under heavy loadThomas Richter
Machines with a larger number of CPUs and under heavy load sometimes loose PAI counter increments during recording using events -e CRYPTO_ÂLL or -e NNPA_ALL. Counting is not affected. This happens when several PAI crypto counters are incremented during the same cryptographic operation. During schedule out the functions paiXXX_sched_task() (with XXX either crypt or ext) +--> pai_have_samples() +--> pai_have_sample() +--> pai_copy() +--> pai_push_sample() are called to read out PAI counter values. In pai_copy() the current values of PAI counters are read from the PMU memory mapped page and compared to the values read during last schedule out operation, which have been saved in a backup page named PAI_SAVE_AREA(event). For each PAI counter a delta is calculated and when the delta is positive, that PAI counter was incremented by hardware. This positve delta is reported as raw data record attached to a sample. After all deltas have been calculated, the new PAI counter values are saved in the backup page PAI_SAVE_AREA(event). However this is done in pai_push_sample(), leaving a small window for missing hardware triggered updates. Here is one scenario: PAI counter idx: 0 1 2 3 4 5 6 7 .... N +---+---+---+---+---+---+---+---+ +---+ PAI counter page:| | | X | | | | | |....| Y | +---+---+---+---+---+---+---+---+ +---+ In pai_copy() each PAI counter value is read and compared to its old value. This is done in a loop. When PAI counter indexed N is read, the hardware might increment PAI counter indexed 2 again, updating its value from X to X+1. Later pai_push_sample() simply mem-copies the complete PAI counter page to a backup page and the increment of X+1 is lost, because the backup page now contains the new value. Read each PAI counter and save this value in the backup page when there is a positive delta. This omits any time window between read and store. This also reduced the work load as only modified PAI counters are saved. Cc: stable@vger.kernel.org Fixes: fe861b0c8d06 ("s390/pai: save PAI counter value page in event structure") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-05s390: Remove extra check of task_stack_page()Maninder Singh
There is no need to call task_stack_page(), because try_get_task_stack() already takes care of that. Signed-off-by: Maninder Singh <maninder1.s@samsung.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-04-30s390/pai: Disable duplicate read of kernel PAI counter valueThomas Richter
The PAI crypto counter design allows for user space and kernel space PAI counter increment recording. This is achieved by splitting the recording page in half. The upper part of the 4KB page records user space increments of PAI crypto counter and the lower half records kernel space increments. The page itself looks like: lowcore ptr ---> ++++++++++++++++++++++++ |user space area | +----------------------+ |kernel space area | ++++++++++++++++++++++++ User space and kernel space entries are handled via a kernel_offset value when wrting. For PAI crypto counters this offset is 2048 or half of a page size. For PAI NNPA counter design this distinction was not needed. There is no user and kernel space part for the page pointed to by lowcore. The set up is: lowcore ptr ---> ++++++++++++++++++++++++ |user + kernel space | |area | | | ++++++++++++++++++++++++ There is always only one counter value recorded and saved. Depending on number of CPUs and machine load, the number of PAI NNPA counter increment differs between counting (perf stat) and recording (perf record). The number reported by sampling was double the number shown by counting. This was caused by a double read of the PAI NNPA values in function pai_copy(). The first part of that function reads the kernel space part. The offset into the kernel page part must be larger than zero. The second part of that function reads the user space part, which begins of offset zero. This works fine for PAI crypto counters. It fails for PAI NNPA counters because the PMU device driver does not support that feature and has a kernel_offset value of 0x0. Executing both user and kernel space read out might end up reading user space value twice. For the PAI NNPA PMU prohibit the kernel space part read out. Cc: stable@vger.kernel.org Fixes: f12473541356 ("s390/pai_crypto: Rename paicrypt_copy() to pai_copy()") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-04-28s390/debug: Reject zero-length input in debug_input_flush_fn()Vasily Gorbik
debug_input_flush_fn() always copies one byte from the userspace buffer with copy_from_user() regardless of the supplied write length. A zero-length write therefore reads one byte beyond the caller's buffer. If the stale byte happens to be '-' or a digit the debug log is silently flushed. With an unmapped buffer the call returns -EFAULT. Reject zero-length writes before copying from userspace. Cc: stable@vger.kernel.org # v5.10+ Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-04-28s390/debug: Reject zero-length input before trimming a newlinePengpeng Hou
debug_get_user_string() duplicates the userspace buffer with memdup_user_nul() and then unconditionally looks at buffer[user_len - 1] to strip a trailing newline. A zero-length write reaches this helper unchanged, so the newline trim reads before the start of the allocated buffer. Reject empty writes before accessing the last input byte. Fixes: 66a464dbc8e0 ("[PATCH] s390: debug feature changes") Cc: stable@vger.kernel.org Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Tested-by: Vasily Gorbik <gor@linux.ibm.com> Link: https://lore.kernel.org/r/20260417073530.96002-1-pengpeng@iscas.ac.cn Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-04-17Merge tag 'integrity-v7.1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull integrity updates from Mimi Zohar: "There are two main changes, one feature removal, some code cleanup, and a number of bug fixes. Main changes: - Detecting secure boot mode was limited to IMA. Make detecting secure boot mode accessible to EVM and other LSMs - IMA sigv3 support was limited to fsverity. Add IMA sigv3 support for IMA regular file hashes and EVM portable signatures Remove: - Remove IMA support for asychronous hash calculation originally added for hardware acceleration Cleanup: - Remove unnecessary Kconfig CONFIG_MODULE_SIG and CONFIG_KEXEC_SIG tests - Add descriptions of the IMA atomic flags Bug fixes: - Like IMA, properly limit EVM "fix" mode - Define and call evm_fix_hmac() to update security.evm - Fallback to using i_version to detect file change for filesystems that do not support STATX_CHANGE_COOKIE - Address missing kernel support for configured (new) TPM hash algorithms - Add missing crypto_shash_final() return value" * tag 'integrity-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: evm: Enforce signatures version 3 with new EVM policy 'bit 3' integrity: Allow sigv3 verification on EVM_XATTR_PORTABLE_DIGSIG ima: add support to require IMA sigv3 signatures ima: add regular file data hash signature version 3 support ima: Define asymmetric_verify_v3() to verify IMA sigv3 signatures ima: remove buggy support for asynchronous hashes integrity: Eliminate weak definition of arch_get_secureboot() ima: Add code comments to explain IMA iint cache atomic_flags ima_fs: Correctly create securityfs files for unsupported hash algos ima: check return value of crypto_shash_final() in boot aggregate ima: Define and use a digest_size field in the ima_algo_desc structure powerpc/ima: Drop unnecessary check for CONFIG_MODULE_SIG ima: efi: Drop unnecessary check for CONFIG_MODULE_SIG/CONFIG_KEXEC_SIG ima: fallback to using i_version to detect file change evm: fix security.evm for a file with IMA signature s390: Drop unnecessary CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT evm: Don't enable fix mode when secure boot is enabled integrity: Make arch_ima_get_secureboot integrity-wide
2026-04-14Merge tag 'bpf-next-7.1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Pull bpf updates from Alexei Starovoitov: - Welcome new BPF maintainers: Kumar Kartikeya Dwivedi, Eduard Zingerman while Martin KaFai Lau reduced his load to Reviwer. - Lots of fixes everywhere from many first time contributors. Thank you All. - Diff stat is dominated by mechanical split of verifier.c into multiple components: - backtrack.c: backtracking logic and jump history - states.c: state equivalence - cfg.c: control flow graph, postorder, strongly connected components - liveness.c: register and stack liveness - fixups.c: post-verification passes: instruction patching, dead code removal, bpf_loop inlining, finalize fastcall 8k line were moved. verifier.c still stands at 20k lines. Further refactoring is planned for the next release. - Replace dynamic stack liveness with static stack liveness based on data flow analysis. This improved the verification time by 2x for some programs and equally reduced memory consumption. New logic is in liveness.c and supported by constant folding in const_fold.c (Eduard Zingerman, Alexei Starovoitov) - Introduce BTF layout to ease addition of new BTF kinds (Alan Maguire) - Use kmalloc_nolock() universally in BPF local storage (Amery Hung) - Fix several bugs in linked registers delta tracking (Daniel Borkmann) - Improve verifier support of arena pointers (Emil Tsalapatis) - Improve verifier tracking of register bounds in min/max and tnum domains (Harishankar Vishwanathan, Paul Chaignon, Hao Sun) - Further extend support for implicit arguments in the verifier (Ihor Solodrai) - Add support for nop,nop5 instruction combo for USDT probes in libbpf (Jiri Olsa) - Support merging multiple module BTFs (Josef Bacik) - Extend applicability of bpf_kptr_xchg (Kaitao Cheng) - Retire rcu_trace_implies_rcu_gp() (Kumar Kartikeya Dwivedi) - Support variable offset context access for 'syscall' programs (Kumar Kartikeya Dwivedi) - Migrate bpf_task_work and dynptr to kmalloc_nolock() (Mykyta Yatsenko) - Fix UAF in in open-coded task_vma iterator (Puranjay Mohan) * tag 'bpf-next-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (241 commits) selftests/bpf: cover short IPv4/IPv6 inputs with adjust_room bpf: reject short IPv4/IPv6 inputs in bpf_prog_test_run_skb selftests/bpf: Use memfd_create instead of shm_open in cgroup_iter_memcg selftests/bpf: Add test for cgroup storage OOB read bpf: Fix OOB in pcpu_init_value selftests/bpf: Fix reg_bounds to match new tnum-based refinement selftests/bpf: Add tests for non-arena/arena operations bpf: Allow instructions with arena source and non-arena dest registers bpftool: add missing fsession to the usage and docs of bpftool docs/bpf: add missing fsession attach type to docs bpf: add missing fsession to the verifier log bpf: Move BTF checking logic into check_btf.c bpf: Move backtracking logic to backtrack.c bpf: Move state equivalence logic to states.c bpf: Move check_cfg() into cfg.c bpf: Move compute_insn_live_regs() into liveness.c bpf: Move fixup/post-processing logic from verifier.c into fixups.c bpf: Simplify do_check_insn() bpf: Move checks for reserved fields out of the main pass bpf: Delete unused variable ...
2026-04-14Merge tag 'modules-7.1-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux Pull module updates from Sami Tolvanen: "Kernel symbol flags: - Replace the separate *_gpl symbol sections (__ksymtab_gpl and __kcrctab_gpl) with a unified symbol table and a new __kflagstab section. This section stores symbol flags, such as the GPL-only flag, as an 8-bit bitset for each exported symbol. This is a cleanup that simplifies symbol lookup in the module loader by avoiding table fragmentation and will allow a cleaner way to add more flags later if needed. Module signature UAPI: - Move struct module_signature to the UAPI headers to allow reuse by tools outside the kernel proper, such as kmod and scripts/sign-file. This also renames a few constants for clarity and drops unused signature types as preparation for hash-based module integrity checking work that's in progress. Sysfs: - Add a /sys/module/<module>/import_ns sysfs attribute to show the symbol namespaces imported by loaded modules. This makes it easier to verify driver API access at runtime on systems that care about such things (e.g. Android). Cleanups and fixes: - Force sh_addr to 0 for all sections in module.lds. This prevents non-zero section addresses when linking modules with 'ld.bfd -r', which confused elfutils. - Fix a memory leak of charp module parameters on module unload when the kernel is configured with CONFIG_SYSFS=n. - Override the -EEXIST error code returned by module_init() to userspace. This prevents confusion with the errno reserved by the module loader to indicate that a module is already loaded. - Simplify the warning message and drop the stack dump on positive returns from module_init(). - Drop unnecessary extern keywords from function declarations and synchronize parse_args() arguments with their implementation" * tag 'modules-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux: (23 commits) module: Simplify warning on positive returns from module_init() module: Override -EEXIST module return documentation: remove references to *_gpl sections module: remove *_gpl sections from vmlinux and modules module: deprecate usage of *_gpl sections in module loader module: use kflagstab instead of *_gpl sections module: populate kflagstab in modpost module: add kflagstab section to vmlinux and modules module: define ksym_flags enumeration to represent kernel symbol flags selftests/bpf: verify_pkcs7_sig: Use 'struct module_signature' from the UAPI headers sign-file: use 'struct module_signature' from the UAPI headers tools uapi headers: add linux/module_signature.h module: Move 'struct module_signature' to UAPI module: Give MODULE_SIG_STRING a more descriptive name module: Give 'enum pkey_id_type' a more specific name module: Drop unused signature types extract-cert: drop unused definition of PKEY_ID_PKCS7 docs: symbol-namespaces: mention sysfs attribute module: expose imported namespaces via sysfs module: Remove extern keyword from param prototypes ...
2026-04-13Merge tag 'hardening-v7.1-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: - randomize_kstack: Improve implementation across arches (Ryan Roberts) - lkdtm/fortify: Drop unneeded FORTIFY_STR_OBJECT test - refcount: Remove unused __signed_wrap function annotations * tag 'hardening-v7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: lkdtm/fortify: Drop unneeded FORTIFY_STR_OBJECT test refcount: Remove unused __signed_wrap function annotations randomize_kstack: Unify random source across arches randomize_kstack: Maintain kstack_offset per task
2026-04-03Merge tag 's390-7.0-7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 fixes from Vasily Gorbik: - Fix a memory leak in the zcrypt driver where the AP message buffer for clear key RSA requests was allocated twice, once by the caller and again locally, causing the first allocation to never be freed - Fix the cpum_sf perf sampling rate overflow adjustment to clamp the recalculated rate to the hardware maximum, preventing exceptions on heavily loaded systems running with HZ=1000 * tag 's390-7.0-7' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/zcrypt: Fix memory leak with CCA cards used as accelerator s390/cpum_sf: Cap sampling rate to prevent lsctl exception
2026-04-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 7.0-rc6+Alexei Starovoitov
Cross-merge BPF and other fixes after downstream PR. Minor conflict in kernel/bpf/verifier.c Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-03-28Merge tag 's390-7.0-6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 fixes from Vasily Gorbik: - Add array_index_nospec() to syscall dispatch table lookup to prevent limited speculative out-of-bounds access with user-controlled syscall number - Mark array_index_mask_nospec() __always_inline since GCC may emit an out-of-line call instead of the inline data dependency sequence the mitigation relies on - Clear r12 on kernel entry to prevent potential speculative use of user value in system_call, ext/io/mcck interrupt handlers * tag 's390-7.0-6' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/entry: Scrub r12 register on kernel entry s390/syscalls: Add spectre boundary for syscall dispatch table s390/barrier: Make array_index_mask_nospec() __always_inline
2026-03-28s390/entry: Scrub r12 register on kernel entryVasily Gorbik
Before commit f33f2d4c7c80 ("s390/bp: remove TIF_ISOLATE_BP"), all entry handlers loaded r12 with the current task pointer (lg %r12,__LC_CURRENT) for use by the BPENTER/BPEXIT macros. That commit removed TIF_ISOLATE_BP, dropping both the branch prediction macros and the r12 load, but did not add r12 to the register clearing sequence. Add the missing xgr %r12,%r12 to make the register scrub consistent across all entry points. Fixes: f33f2d4c7c80 ("s390/bp: remove TIF_ISOLATE_BP") Cc: stable@kernel.org Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-28s390/syscalls: Add spectre boundary for syscall dispatch tableGreg Kroah-Hartman
The s390 syscall number is directly controlled by userspace, but does not have an array_index_nospec() boundary to prevent access past the syscall function pointer tables. 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: Arnd Bergmann <arnd@arndb.de> Fixes: 56e62a737028 ("s390: convert to generic entry") Cc: stable@kernel.org Assisted-by: gkh_clanker_2000 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Link: https://lore.kernel.org/r/2026032404-sterling-swoosh-43e6@gregkh Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-24randomize_kstack: Unify random source across archesRyan Roberts
Previously different architectures were using random sources of differing strength and cost to decide the random kstack offset. A number of architectures (loongarch, powerpc, s390, x86) were using their timestamp counter, at whatever the frequency happened to be. Other arches (arm64, riscv) were using entropy from the crng via get_random_u16(). There have been concerns that in some cases the timestamp counters may be too weak, because they can be easily guessed or influenced by user space. And get_random_u16() has been shown to be too costly for the level of protection kstack offset randomization provides. So let's use a common, architecture-agnostic source of entropy; a per-cpu prng, seeded at boot-time from the crng. This has a few benefits: - We can remove choose_random_kstack_offset(); That was only there to try to make the timestamp counter value a bit harder to influence from user space [*]. - The architecture code is simplified. All it has to do now is call add_random_kstack_offset() in the syscall path. - The strength of the randomness can be reasoned about independently of the architecture. - Arches previously using get_random_u16() now have much faster syscall paths, see below results. [*] Additionally, this gets rid of some redundant work on s390 and x86. Before this patch, those architectures called choose_random_kstack_offset() under arch_exit_to_user_mode_prepare(), which is also called for exception returns to userspace which were *not* syscalls (e.g. regular interrupts). Getting rid of choose_random_kstack_offset() avoids a small amount of redundant work for the non-syscall cases. In some configurations, add_random_kstack_offset() will now call instrumentable code, so for a couple of arches, I have moved the call a bit later to the first point where instrumentation is allowed. This doesn't impact the efficacy of the mechanism. There have been some claims that a prng may be less strong than the timestamp counter if not regularly reseeded. But the prng has a period of about 2^113. So as long as the prng state remains secret, it should not be possible to guess. If the prng state can be accessed, we have bigger problems. Additionally, we are only consuming 6 bits to randomize the stack, so there are only 64 possible random offsets. I assert that it would be trivial for an attacker to brute force by repeating their attack and waiting for the random stack offset to be the desired one. The prng approach seems entirely proportional to this level of protection. Performance data are provided below. The baseline is v6.18 with rndstack on for each respective arch. (I)/(R) indicate statistically significant improvement/regression. arm64 platform is AWS Graviton3 (m7g.metal). x86_64 platform is AWS Sapphire Rapids (m7i.24xlarge): +-----------------+--------------+---------------+---------------+ | Benchmark | Result Class | per-cpu-prng | per-cpu-prng | | | | arm64 (metal) | x86_64 (VM) | +=================+==============+===============+===============+ | syscall/getpid | mean (ns) | (I) -9.50% | (I) -17.65% | | | p99 (ns) | (I) -59.24% | (I) -24.41% | | | p99.9 (ns) | (I) -59.52% | (I) -28.52% | +-----------------+--------------+---------------+---------------+ | syscall/getppid | mean (ns) | (I) -9.52% | (I) -19.24% | | | p99 (ns) | (I) -59.25% | (I) -25.03% | | | p99.9 (ns) | (I) -59.50% | (I) -28.17% | +-----------------+--------------+---------------+---------------+ | syscall/invalid | mean (ns) | (I) -10.31% | (I) -18.56% | | | p99 (ns) | (I) -60.79% | (I) -20.06% | | | p99.9 (ns) | (I) -61.04% | (I) -25.04% | +-----------------+--------------+---------------+---------------+ I tested an earlier version of this change on x86 bare metal and it showed a smaller but still significant improvement. The bare metal system wasn't available this time around so testing was done in a VM instance. I'm guessing the cost of rdtsc is higher for VMs. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Link: https://patch.msgid.link/20260303150840.3789438-3-ryan.roberts@arm.com Signed-off-by: Kees Cook <kees@kernel.org>
2026-03-24module: Give MODULE_SIG_STRING a more descriptive nameThomas Weißschuh
The purpose of the constant it is not entirely clear from its name. As this constant is going to be exposed in a UAPI header, give it a more specific name for clarity. As all its users call it 'marker', use that wording in the constant itself. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Petr Pavlu <petr.pavlu@suse.com> Reviewed-by: Nicolas Schier <nsc@kernel.org> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
2026-03-24module: Give 'enum pkey_id_type' a more specific nameThomas Weißschuh
This enum originates in generic cryptographic code and has a very generic name. Nowadays it is only used for module signatures. As this enum is going to be exposed in a UAPI header, give it a more specific name for clarity and consistency. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Petr Pavlu <petr.pavlu@suse.com> Reviewed-by: Nicolas Schier <nsc@kernel.org> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
2026-03-24s390/cpum_sf: Cap sampling rate to prevent lsctl exceptionThomas Richter
commit fcc43a7e294f ("s390/configs: Set HZ=1000") changed the interrupt frequency of the system. On machines with heavy load and many perf event overflows, this might lead to an exception. Dmesg displays these entries: [112.242542] cpum_sf: Loading sampling controls failed: op 1 err -22 One line per CPU online. The root cause is the CPU Measurement sampling facility overflow adjustment. Whenever an overflow (too much samples per tick) occurs, the sampling rate is adjusted and increased. This was done without observing the maximum sampling rate limit. When the current sampling interval is higher than the maximum sampling rate limit, the lsctl instruction raises an exception. The error messages is the result of such an exception. Observe the upper limit when the new sampling rate is recalculated. Cc: stable@vger.kernel.org Fixes: 39d4a501a9ef ("s390/cpum_sf: Adjust sampling interval to avoid hitting sample limits") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-24Merge tag 'kvm-s390-master-7.0-1' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD KVM: s390: Fixes for 7.0 - fix deadlock in new memory management - handle kernel faults on donated memory properly - fix bounds checking for irq routing + selftest - fix invalid machine checks + logging
2026-03-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 7.0-rc5Alexei Starovoitov
Cross-merge BPF and other fixes after downstream PR. Minor conflicts in: tools/testing/selftests/bpf/progs/exceptions_fail.c tools/testing/selftests/bpf/progs/verifier_bounds.c Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-03-16KVM: s390: vsie: Avoid injecting machine check on signalChristian Borntraeger
The recent XFER_TO_GUEST_WORK change resulted in a situation, where the vsie code would interpret a signal during work as a machine check during SIE as both use the EINTR return code. The exit_reason of the sie64a function has nothing to do with the kvm_run exit_reason. Rename it and define a specific code for machine checks instead of abusing -EINTR. rename exit_reason into sie_return to avoid the naming conflict and change the code flow in vsie.c to have a separate variable for rc and sie_return. Fixes: 2bd1337a1295e ("KVM: s390: Use generic VIRT_XFER_TO_GUEST_WORK functions") Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
2026-03-13Merge tag 's390-7.0-5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 fixes from Vasily Gorbik: - Revert IRQ entry/exit path optimization that incorrectly cleared some PSW bits before irqentry_exit(), causing boot failures with linux-next and HRTIMER_REARM_DEFERRED (which only uncovered the problem) - Fix zcrypt code to show CCA card serial numbers even when the default crypto domain is offline by selecting any domain available, preventing empty sysfs entries * tag 's390-7.0-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/zcrypt: Enable AUTOSEL_DOM for CCA serialnr sysfs attribute s390: Revert "s390/irq/idle: Remove psw bits early"
2026-03-13integrity: Eliminate weak definition of arch_get_secureboot()Nathan Chancellor
security/integrity/secure_boot.c contains a single __weak function, which breaks recordmcount when building with clang: $ make -skj"$(nproc)" ARCH=powerpc LLVM=1 ppc64_defconfig security/integrity/secure_boot.o Cannot find symbol for section 2: .text. security/integrity/secure_boot.o: failed Introduce a Kconfig symbol, CONFIG_HAVE_ARCH_GET_SECUREBOOT, to indicate that an architecture provides a definition of arch_get_secureboot(). Provide a static inline stub when this symbol is not defined to achieve the same effect as the __weak function, allowing secure_boot.c to be removed altogether. Move the s390 definition of arch_get_secureboot() out of the CONFIG_KEXEC_FILE block to ensure it is always available, as it does not actually depend on KEXEC_FILE. Reported-by: Arnd Bergmann <arnd@arndb.de> Fixes: 31a6a07eefeb ("integrity: Make arch_ima_get_secureboot integrity-wide") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2026-03-08Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 7.0-rc3Alexei Starovoitov
Cross-merge BPF and other fixes after downstream PR. No conflicts. Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-03-07s390: Revert "s390/irq/idle: Remove psw bits early"Heiko Carstens
This reverts commit d8b5cf9c63143fae54a734c41e3bb55cf3f365c7. Mikhail Zaslonko reported that linux-next doesn't boot anymore [2]. Reason for this is recent change [2] was supposed to slightly optimize the irq entry/exit path by removing some psw bits early in case of an idle exit. This however is incorrect since irqentry_exit() requires the correct old psw state at irq entry. Otherwise the embedded regs_irqs_disabled() will not provide the correct result. With linux-next and HRTIMER_REARM_DEFERRED this leads to the observed boot problems, however the commit is broken in any case. Revert the commit which introduced this. Thanks to Peter Zijlstra for pointing out that this is a bug in the s390 entry code. Fixes: d8b5cf9c6314 ("s390/irq/idle: Remove psw bits early") [1] Reported-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Reported-by: Peter Zijlstra <peterz@infradead.org> Closes: https://lore.kernel.org/r/af549a19-db99-4b16-8511-bf315177a13e@linux.ibm.com/ [2] Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Tested-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Acked-by: Vasily Gorbik <gor@linux.ibm.com> Link: https://lore.kernel.org/r/20260306111919.362559-1-hca@linux.ibm.com Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-06Merge tag 'kbuild-fixes-7.0-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux Pull Kbuild fixes from Nathan Chancellor: - Split out .modinfo section from ELF_DETAILS macro, as that macro may be used in other areas that expect to discard .modinfo, breaking certain image layouts - Adjust genksyms parser to handle optional attributes in certain declarations, necessary after commit 07919126ecfc ("netfilter: annotate NAT helper hook pointers with __rcu") - Include resolve_btfids in external module build created by scripts/package/install-extmod-build when it may be run on external modules - Avoid removing objtool binary with 'make clean', as it is required for external module builds * tag 'kbuild-fixes-7.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: kbuild: Leave objtool binary around with 'make clean' kbuild: install-extmod-build: Package resolve_btfids if necessary genksyms: Fix parsing a declarator with a preceding attribute kbuild: Split .modinfo out from ELF_DETAILS
2026-03-05s390: Drop unnecessary CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOTCoiby Xu
Commit b5ca117365d9 ("ima: prevent kexec_load syscall based on runtime secureboot flag") and commit 268a78404973 ("s390/kexec_file: Disable kexec_load when IPLed secure") disabled the kexec_load syscall based on the secureboot mode. Commit 9e2b4be377f0 ("ima: add a new CONFIG for loading arch-specific policies") needed to detect the secure boot mode, not to load an IMA architecture specific policy. Since there is the new CONFIG_INTEGRITY_SECURE_BOOT, drop CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT for s390. Signed-off-by: Coiby Xu <coxu@redhat.com> Tested-by: Alexander Egorenkov <egorenar@linux.ibm.com> [Vasily Gorbik: Fix missing arch_get_secureboot() prototype warning] link: https://lore.kernel.org/linux-integrity/c00-01.ttbfdx5@ub.hpns/ Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2026-03-05integrity: Make arch_ima_get_secureboot integrity-wideCoiby Xu
EVM and other LSMs need the ability to query the secure boot status of the system, without directly calling the IMA arch_ima_get_secureboot function. Refactor the secure boot status check into a general function named arch_get_secureboot. Reported-and-suggested-by: Mimi Zohar <zohar@linux.ibm.com> Suggested-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Coiby Xu <coxu@redhat.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2026-03-03s390: Introduce bpf_get_lowcore() kfuncIlya Leoshkevich
Implementing BPF version of preempt_count() requires accessing lowcore from BPF. Since lowcore can be relocated, open-coding (struct lowcore *)0 does not work, so add a kfunc. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Link: https://lore.kernel.org/r/20260217160813.100855-2-iii@linux.ibm.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-02-26kbuild: Split .modinfo out from ELF_DETAILSNathan Chancellor
Commit 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") added .modinfo to ELF_DETAILS while removing it from COMMON_DISCARDS, as it was needed in vmlinux.unstripped and ELF_DETAILS was present in all architecture specific vmlinux linker scripts. While this shuffle is fine for vmlinux, ELF_DETAILS and COMMON_DISCARDS may be used by other linker scripts, such as the s390 and x86 compressed boot images, which may not expect to have a .modinfo section. In certain circumstances, this could result in a bootloader failing to load the compressed kernel [1]. Commit ddc6cbef3ef1 ("s390/boot/vmlinux.lds.S: Ensure bzImage ends with SecureBoot trailer") recently addressed this for the s390 bzImage but the same bug remains for arm, parisc, and x86. The presence of .modinfo in the x86 bzImage was the root cause of the issue worked around with commit d50f21091358 ("kbuild: align modinfo section for Secureboot Authenticode EDK2 compat"). misc.c in arch/x86/boot/compressed includes lib/decompress_unzstd.c, which in turn includes lib/xxhash.c and its MODULE_LICENSE / MODULE_DESCRIPTION macros due to the STATIC definition. Split .modinfo out from ELF_DETAILS into its own macro and handle it in all vmlinux linker scripts. Discard .modinfo in the places where it was previously being discarded from being in COMMON_DISCARDS, as it has never been necessary in those uses. Cc: stable@vger.kernel.org Fixes: 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") Reported-by: Ed W <lists@wildgooses.com> Closes: https://lore.kernel.org/587f25e0-a80e-46a5-9f01-87cb40cfa377@wildgooses.com/ [1] Tested-by: Ed W <lists@wildgooses.com> # x86_64 Link: https://patch.msgid.link/20260225-separate-modinfo-from-elf-details-v1-1-387ced6baf4b@kernel.org Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2026-02-25s390/kexec: Disable stack protector in s390_reset_system()Vasily Gorbik
s390_reset_system() calls set_prefix(0), which switches back to the absolute lowcore. At that point the stack protector canary no longer matches the canary from the lowcore the function was entered with, so the stack check fails. Mark s390_reset_system() __no_stack_protector. This is safe here since its callers (__do_machine_kdump() and __do_machine_kexec()) are effectively no-return and fall back to disabled_wait() on failure. Fixes: f5730d44e05e ("s390: Add stackprotector support") Reported-by: Nikita Dubrovskii <nikita@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-02-25s390/vtime: Use lockdep_assert_irqs_disabled() instead of BUG_ON()Heiko Carstens
Use lockdep_assert_irqs_disabled() instead of BUG_ON(). This avoids crashing the kernel, and generates better code if CONFIG_PROVE_LOCKING is disabled. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>