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2023-02-14vfio/ccw: remove WARN_ON during shutdownEric Farman
The logic in vfio_ccw_sch_shutdown() always assumed that the input subchannel would point to a vfio_ccw_private struct, without checking that one exists. The blamed commit put in a check for this scenario, to prevent the possibility of a missing private. The trouble is that check was put alongside a WARN_ON(), presuming that such a scenario would be a cause for concern. But this can be triggered by binding a subchannel to vfio-ccw, and rebooting the system before starting the mdev (via "mdevctl start" or similar) or after stopping it. In those cases, shutdown doesn't need to worry because either the private was never allocated, or it was cleaned up by vfio_ccw_mdev_remove(). Remove the WARN_ON() piece of this check, since there are plausible scenarios where private would be NULL in this path. Fixes: 9e6f07cd1eaa ("vfio/ccw: create a parent struct") Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Link: https://lore.kernel.org/r/20230210174227.2256424-1-farman@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-14s390/entry: remove toolchain dependent micro-optimizationHeiko Carstens
Get rid of CONFIG_AS_IS_LLVM in entry.S to make the code a bit more readable. This removes a micro-optimization, but given that the llvm IAS limitation will likely stay, just use the version that works with llvm. See commit 4c25f0ff6336 ("s390/entry: workaround llvm's IAS limitations") for further details. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-14s390/mem_detect: do not truncate online memory ranges infoVasily Gorbik
Commit bf64f0517e5d ("s390/mem_detect: handle online memory limit just once") introduced truncation of mem_detect online ranges based on identity mapping size. For kdump case however the full set of online memory ranges has to be feed into memblock_physmem_add so that crashed system memory could be extracted. Instead of truncating introduce a "usable limit" which is respected by mem_detect api. Also add extra online memory ranges iterator which still provides full set of online memory ranges disregarding the "usable limit". Fixes: bf64f0517e5d ("s390/mem_detect: handle online memory limit just once") Reported-by: Alexander Egorenkov <egorenar@linux.ibm.com> Tested-by: Alexander Egorenkov <egorenar@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-14s390/vx: remove __uint128_t type from __vector128 struct againHeiko Carstens
The __uint128_t member was only added for future convenience to the __vector128 struct. However this is a uapi header file, 31/32 bit (aka compat layer) is still supported, but doesn't know anything about this type: /usr/include/asm/types.h:27:17: error: unknown type name __uint128_t 27 | __uint128_t v; Therefore remove it again. Fixes: b0b7b43fcc46 ("s390/vx: add 64 and 128 bit members to __vector128 struct") Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-14s390/mm: add support for RDP (Reset DAT-Protection)Gerald Schaefer
RDP instruction allows to reset DAT-protection bit in a PTE, with less CPU synchronization overhead than IPTE instruction. In particular, IPTE can cause machine-wide synchronization overhead, and excessive IPTE usage can negatively impact machine performance. RDP can be used instead of IPTE, if the new PTE only differs in SW bits and _PAGE_PROTECT HW bit, for PTE protection changes from RO to RW. SW PTE bit changes are allowed, e.g. for dirty and young tracking, but none of the other HW-defined part of the PTE must change. This is because the architecture forbids such changes to an active and valid PTE, which is why invalidation with IPTE is always used first, before writing a new entry. The RDP optimization helps mainly for fault-driven SW dirty-bit tracking. Writable PTEs are initially always mapped with HW _PAGE_PROTECT bit set, to allow SW dirty-bit accounting on first write protection fault, where the DAT-protection would then be reset. The reset is now done with RDP instead of IPTE, if RDP instruction is available. RDP cannot always guarantee that the DAT-protection reset is propagated to all CPUs immediately. This means that spurious TLB protection faults on other CPUs can now occur. For this, common code provides a flush_tlb_fix_spurious_fault() handler, which will now be used to do a CPU-local TLB flush. However, this will clear the whole TLB of a CPU, and not just the affected entry. For more fine-grained flushing, by simply doing a (local) RDP again, flush_tlb_fix_spurious_fault() would need to also provide the PTE pointer. Note that spurious TLB protection faults cannot really be distinguished from racing pagetable updates, where another thread already installed the correct PTE. In such a case, the local TLB flush would be unnecessary overhead, but overall reduction of CPU synchronization overhead by not using IPTE is still expected to be beneficial. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-14s390/mm: define private VM_FAULT_* reasons from top bitsPeter Xu
The current definition already collapse with the generic definition of vm_fault_reason. Move the private definitions to allocate bits from the top of uint so they won't collapse anymore. Signed-off-by: Peter Xu <peterx@redhat.com> Link: https://lore.kernel.org/r/20230205231704.909536-4-peterx@redhat.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-10Documentation: s390: correct spellingRandy Dunlap
Correct spelling problems for Documentation/s390/ as reported by codespell. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20230209071400.31476-16-rdunlap@infradead.org Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-10s390/ap: fix status returned by ap_qact()Halil Pasic
Since commit 159491f3b509 ("s390/ap: rework assembler functions to use unions for in/out register variables") the function ap_qact() tries to grab the status from the wrong part of the register. Thus we always end up with zeros. Which is wrong, among others, because we detect failures via status.response_code. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reported-by: Harald Freudenberger <freude@linux.ibm.com> Fixes: 159491f3b509 ("s390/ap: rework assembler functions to use unions for in/out register variables") Reviewed-by: Harald Freudenberger <freude@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-10s390/ap: fix status returned by ap_aqic()Halil Pasic
There function ap_aqic() tries to grab the status from the wrong part of the register. Thus we always end up with zeros. Which is wrong, among others, because we detect failures via status.response_code. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reported-by: Janosch Frank <frankja@linux.ibm.com> Fixes: 159491f3b509 ("s390/ap: rework assembler functions to use unions for in/out register variables") Reviewed-by: Harald Freudenberger <freude@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-10s390: vfio-ap: tighten the NIB validity checkHalil Pasic
The NIB is architecturally invalid if the address designates a storage location that is not installed or if it is zero. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reported-by: Janosch Frank <frankja@linux.ibm.com> Fixes: ec89b55e3bce ("s390: ap: implement PAPQ AQIC interception in kernel") Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09Revert "s390/mem_detect: do not update output parameters on failure"Heiko Carstens
This reverts commit cbc29f107e51b1cc7d1e7b0bbe0691a1224205f1. Get rid of the following smatch warnings: arch/s390/include/asm/mem_detect.h:86 get_mem_detect_end() error: uninitialized symbol 'end'. arch/s390/include/asm/mem_detect.h:86 get_mem_detect_end() error: uninitialized symbol 'end'. arch/s390/boot/vmem.c:256 setup_vmem() error: uninitialized symbol 'start'. arch/s390/boot/vmem.c:258 setup_vmem() error: uninitialized symbol 'end'. Note that there is no bug in the code. This is purely to silence smatch. Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09s390/idle: remove arch_cpu_idle_time() and corresponding codeHeiko Carstens
arch_cpu_idle_time() returns the idle time of any given cpu if it is in idle, or zero if not. All if this is racy and partially incorrect. Time stamps taken with store clock extended and store clock fast from different cpus are compared, while the architecture states that this is nothing which can be relied on (see Principles of Operation; Chapter 4, "Setting and Inspecting the Clock"). A more fundamental problem is that the timestamp when a cpu is leaving idle is taken early in the assembler part of the interrupt handler, and this value is only transferred many cycles later to the cpu's per-cpu idle data structure. This per cpu data structure is read by arch_cpu_idle() to tell for which period of time a remote cpu is idle: if only an idle_enter value is present, the assumed idle time of the cpu is calculated by taking a local timestamp and returning the difference of the local timestamp and the idle_enter value. This is potentially incorrect, since the remote cpu may have already left idle, but the taken timestamp may not have been transferred to the per-cpu data structure. This in turn means that too much idle time may be reported for a cpu, and a subsequent calculation of system idle time may result in a smaller value. Instead of coming up with even more complex code trying to fix this, just remove this code, and only account idle time of a cpu, after idle state is left. Another minor bug is that it is assumed that timestamps are non-zero, which is not necessarily the case for timestamps taken with store clock fast. This however is just a very minor problem, since this can only happen when the epoch increases. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09s390/vx: use simple assignments to access __vector128 membersHeiko Carstens
Use simple assignments to access __vector128 members instead of hard to read casts. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09s390/vx: add 64 and 128 bit members to __vector128 structHeiko Carstens
Add 64 and 128 bit members to __vector128 struct in order to allow reading of the complete value, or the higher or lower part of vector register contents instead of having to use casts. Add an explicit __aligned(4) statement to avoid that the alignment of the structure changes from 4 to 8. This should make sure that no breakage happens because of this change. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09MAINTAINERS: add diag288_wdt driver to s390 maintained filesHeiko Carstens
The diag288_wdt watchdog driver is s390 specific. Document who is responsible for this driver. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09MAINTAINERS: add entry for s390 SCM driverVineeth Vijayan
Storage Class Memory driver support for s390 architecture has been there for a while. The original author of this work, Sebastian Ott has left IBM and I am taking over this module. Adding myself as the upstream maintainer for SCM on s390 architecture. Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09s390/processor: always inline cpu flag helper functionsHeiko Carstens
arch_cpu_idle() is marked noinstr and therefore must only call functions which are also not instrumented. Make sure that cpu flag helper functions are always inlined to avoid that the compiler generates an out-of-line function for e.g. the call within arch_cpu_idle(). Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09s390/idle: mark arch_cpu_idle() noinstrHeiko Carstens
linux-next commit ("cpuidle: tracing: Warn about !rcu_is_watching()") adds a new warning which hits on s390's arch_cpu_idle() function: RCU not on for: arch_cpu_idle+0x0/0x28 WARNING: CPU: 2 PID: 0 at include/linux/trace_recursion.h:162 arch_ftrace_ops_list_func+0x24c/0x258 Modules linked in: CPU: 2 PID: 0 Comm: swapper/2 Not tainted 6.2.0-rc6-next-20230202 #4 Hardware name: IBM 8561 T01 703 (z/VM 7.3.0) Krnl PSW : 0404d00180000000 00000000002b55c0 (arch_ftrace_ops_list_func+0x250/0x258) R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3 Krnl GPRS: c0000000ffffbfff 0000000080000002 0000000000000026 0000000000000000 0000037ffffe3a28 0000037ffffe3a20 0000000000000000 0000000000000000 0000000000000000 0000000000f4acf6 00000000001044f0 0000037ffffe3cb0 0000000000000000 0000000000000000 00000000002b55bc 0000037ffffe3bb8 Krnl Code: 00000000002b55b0: c02000840051 larl %r2,0000000001335652 00000000002b55b6: c0e5fff512d1 brasl %r14,0000000000157b58 #00000000002b55bc: af000000 mc 0,0 >00000000002b55c0: a7f4ffe7 brc 15,00000000002b558e 00000000002b55c4: 0707 bcr 0,%r7 00000000002b55c6: 0707 bcr 0,%r7 00000000002b55c8: eb6ff0480024 stmg %r6,%r15,72(%r15) 00000000002b55ce: b90400ef lgr %r14,%r15 Call Trace: [<00000000002b55c0>] arch_ftrace_ops_list_func+0x250/0x258 ([<00000000002b55bc>] arch_ftrace_ops_list_func+0x24c/0x258) [<0000000000f5f0fc>] ftrace_common+0x1c/0x20 [<00000000001044f6>] arch_cpu_idle+0x6/0x28 [<0000000000f4acf6>] default_idle_call+0x76/0x128 [<00000000001cc374>] do_idle+0xf4/0x1b0 [<00000000001cc6ce>] cpu_startup_entry+0x36/0x40 [<0000000000119d00>] smp_start_secondary+0x140/0x150 [<0000000000f5d2ae>] restart_int_handler+0x6e/0x90 Mark arch_cpu_idle() noinstr like all other architectures with CONFIG_ARCH_WANTS_NO_INSTR (should) have it to fix this. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09s390/idle: move idle time accounting to account_idle_time_irq()Heiko Carstens
There is no reason to do idle time accounting in arch_cpu_idle(). Do idle time accounting in account_idle_time_irq(), where it belongs to. The accounted values don't change between account_idle_time_irq() and arch_cpu_idle(); so the result is the same. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-09Merge branch 'cmpxchg_user_key' into featuresHeiko Carstens
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06watchdog: diag288_wdt: unify lpar and zvm diag288 helpersAlexander Egorenkov
Change naming of the internal diag288 helper functions to improve overall readability and reduce confusion: * Rename __diag288() to diag288(). * Get rid of the misnamed helper __diag288_lpar() that was used not only on LPARs but also zVM and KVM systems. * Rename __diag288_vm() to diag288_str(). Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20230203073958.1585738-6-egorenar@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06watchdog: diag288_wdt: de-duplicate diag_stat_inc() callsAlexander Egorenkov
Call diag_stat_inc() from __diag288() to reduce code duplication. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20230203073958.1585738-5-egorenar@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06watchdog: diag288_wdt: unify command buffer handling for diag288 zvmAlexander Egorenkov
Simplify and de-duplicate code by introducing a common single command buffer allocated once at initialization. Moreover, simplify the interface of __diag288_vm() by accepting ASCII strings as the command parameter and converting it to the EBCDIC format within the function itself. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20230203073958.1585738-4-egorenar@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06watchdog: diag288_wdt: remove power managementAlexander Egorenkov
Remove power management because s390 no longer supports hibernation since commit 394216275c7d ("s390: remove broken hibernate / power management support"). Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20230203073958.1585738-3-egorenar@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06watchdog: diag288_wdt: get rid of register asmAlexander Egorenkov
Using register asm statements has been proven to be very error prone, especially when using code instrumentation where gcc may add function calls, which clobbers register contents in an unexpected way. Therefore, get rid of register asm statements in watchdog code, and make sure this bug class cannot happen. Moreover, remove the register r1 from the clobber list because this register is not changed by DIAG 288. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20230203073958.1585738-2-egorenar@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06Merge branch 'fixes' into featuresHeiko Carstens
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/boot: avoid potential amode31 truncationVasily Gorbik
Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/boot: move detect_facilities() after cmd line parsingVasily Gorbik
Facilities setup has to be done after "facilities" command line option parsing, it might set extra or remove existing facilities bits for testing purposes. Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/kasan: avoid mapping KASAN shadow for standby memoryVasily Gorbik
KASAN common code is able to handle memory hotplug and create KASAN shadow memory on a fly. Online memory ranges are available from mem_detect, use this information to avoid mapping KASAN shadow for standby memory. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/boot: avoid page tables memory in kaslrVasily Gorbik
If kernel is build without KASAN support there is a chance that kernel image is going to be positioned by KASLR code to overlap with identity mapping page tables. When kernel is build with KASAN support enabled memory which is potentially going to be used for page tables and KASAN shadow mapping is accounted for in KASLR with the use of kasan_estimate_memory_needs(). Split this function and introduce vmem_estimate_memory_needs() to cover decompressor's vmem identity mapping page tables. Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/mem_detect: add get_mem_detect_online_total()Vasily Gorbik
Add a function to get online memory in total. It is supposed to be used in the decompressor as well as during early kernel startup. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/mem_detect: handle online memory limit just onceVasily Gorbik
Introduce mem_detect_truncate() to cut any online memory ranges above established identity mapping size, so that mem_detect users wouldn't have to do it over and over again. Suggested-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/boot: fix mem_detect extended area allocationVasily Gorbik
Allocation of mem_detect extended area was not considered neither in commit 9641b8cc733f ("s390/ipl: read IPL report at early boot") nor in commit b2d24b97b2a9 ("s390/kernel: add support for kernel address space layout randomization (KASLR)"). As a result mem_detect extended theoretically may overlap with ipl report or randomized kernel image position. But as mem_detect code will allocate extended area only upon exceeding 255 online regions (which should alternate with offline memory regions) it is not seen in practice. To make sure mem_detect extended area does not overlap with ipl report or randomized kernel position extend usage of "safe_addr". Make initrd handling and mem_detect extended area allocation code move it further right and make KASLR takes in into consideration as well. Fixes: 9641b8cc733f ("s390/ipl: read IPL report at early boot") Fixes: b2d24b97b2a9 ("s390/kernel: add support for kernel address space layout randomization (KASLR)") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/mem_detect: rely on diag260() if sclp_early_get_memsize() failsVasily Gorbik
In case sclp_early_get_memsize() fails but diag260() succeeds make sure some sane value is returned. This error scenario is highly unlikely, but this change makes system able to boot in such case. Suggested-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/diag: make __diag8c_tmp_amode31 staticHeiko Carstens
Get rid of this sparse warning: arch/s390/kernel/diag.c:69:29: warning: symbol '__diag8c_tmp_amode31' was not declared. Should it be static? Fixes: fbaee7464fbb ("s390/tty3270: add support for diag 8c") Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/rethook: add local rethook header fileHeiko Carstens
Compiling the kernel with CONFIG_KPROBES disabled, but CONFIG_RETHOOK enabled, results in this sparse warning: arch/s390/kernel/rethook.c:26:15: warning: no previous prototype for 'arch_rethook_trampoline_callback' [-Wmissing-prototypes] 26 | unsigned long arch_rethook_trampoline_callback(struct pt_regs *regs) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Add a local rethook header file similar to riscv to address this. Reported-by: kernel test robot <lkp@intel.com> Fixes: 1a280f48c0e4 ("s390/kprobes: replace kretprobe with rethook") Link: https://lore.kernel.org/all/202302030102.69dZIuJk-lkp@intel.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/vmem: remove unnecessary KASAN checksVasily Gorbik
Kasan shadow memory area has been moved to the end of kernel address space since commit 9a39abb7c9aa ("s390/boot: simplify and fix kernel memory layout setup"), therefore skipping any memory ranges above VMALLOC_START in empty page tables cleanup code already handles KASAN shadow memory intersection case and explicit checks could be removed. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/vmem: fix empty page tables cleanup under KASANVasily Gorbik
Commit b9ff81003cf1 ("s390/vmem: cleanup empty page tables") introduced empty page tables cleanup in vmem code, but when the kernel is built with KASAN enabled the code has no effect due to wrong KASAN shadow memory intersection condition, which effectively ignores any memory range below KASAN shadow. Fix intersection condition to make code work as anticipated. Fixes: b9ff81003cf1 ("s390/vmem: cleanup empty page tables") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/kasan: update kasan memory layout noteVasily Gorbik
Kasan shadow memory area has been moved to the end of kernel address space since commit 9a39abb7c9aa ("s390/boot: simplify and fix kernel memory layout setup"). Change kasan memory layout note accordingly. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/mem_detect: fix detect_memory() error handlingVasily Gorbik
Currently if for some reason sclp_early_read_info() fails, sclp_early_get_memsize() will not set max_physmem_end and it will stay uninitialized. Any garbage value other than 0 will lead to detect_memory() taking wrong path or returning a garbage value as max_physmem_end. To avoid that simply initialize max_physmem_end. Fixes: 73045a08cf55 ("s390: unify identity mapping limits handling") Reported-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/hmcdrv: use strscpy() instead of strlcpy()Heiko Carstens
Given that strlcpy() is deprecated use strscpy() instead. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/ipl: add loadparm parameter to eckd ipl/reipl dataSven Schnelle
commit 87fd22e0ae92 ("s390/ipl: add eckd support") missed to add the loadparm attribute to the new eckd ipl/reipl data. Fixes: 87fd22e0ae92 ("s390/ipl: add eckd support") Cc: <stable@vger.kernel.org> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-02-06s390/ipl: add DEFINE_GENERIC_LOADPARM()Sven Schnelle
In the current code each reipl type implements its own pair of loadparm show/store functions. Add a macro to deduplicate the code a bit. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Fixes: 87fd22e0ae92 ("s390/ipl: add eckd support") Cc: <stable@vger.kernel.org> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-31s390/mem_detect: do not update output parameters on failureAlexander Gordeev
Function __get_mem_detect_block() resets start and end output parameters in case of invalid mem_detect array index is provided. That violates the rule of sparing the output on fail path and leads e.g to a below anomaly: for_each_mem_detect_block(i, &start, &end) continue; One would expect start and end contain addresses of the last memory block (if available), but in fact the two will be reset to zeroes. That is not how an iterator is expected to work. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-31s390/cio: introduce locking for register/unregister functionsVineeth Vijayan
Unbinding an I/O subchannel with a child-CCW device in disconnected state sometimes causes a kernel-panic. The race condition was seen mostly during testing, when setting all the CHPIDs of a device to offline and at the same time, the unbinding the I/O subchannel driver. The kernel-panic occurs because of double delete, the I/O subchannel driver calls device_del on the CCW device while another device_del invocation for the same device is in-flight. For instance, disabling all the CHPIDs will trigger the ccw_device_remove function, which will call a ccw_device_unregister(), which ends up calling the device_del() which is asynchronous via cdev's todo workqueue. And unbinding the I/O subchannel driver calls io_subchannel_remove() function which calls the ccw_device_unregister() and device_del(). This double delete can be prevented by serializing all CCW device registration/unregistration calls into the driver core. This patch introduces a mutex which will be used for this purpose. Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com> Reported-by: Boris Fiuczynski <fiuczy@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-31s390/mm,ptdump: avoid Kasan vs Memcpy Real markers swappingVasily Gorbik
---[ Real Memory Copy Area Start ]--- 0x001bfffffffff000-0x001c000000000000 4K PTE I ---[ Kasan Shadow Start ]--- ---[ Real Memory Copy Area End ]--- 0x001c000000000000-0x001c000200000000 8G PMD RW NX ... ---[ Kasan Shadow End ]--- ptdump does a stable sort of markers. Move kasan markers after memcpy real to avoid swapping. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-31s390/boot: remove pgtable_populate_endVasily Gorbik
setup_vmem() already calls populate for all online memory regions. pgtable_populate_end() could be removed. Also rename pgtable_populate_begin() to pgtable_populate_init(). Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-31s390/boot: avoid mapping standby memoryVasily Gorbik
Commit bb1520d581a3 ("s390/mm: start kernel with DAT enabled") doesn't consider online memory holes due to potential memory offlining and erroneously creates pgtables for stand-by memory, which bear RW+X attribute and trigger a warning: RANGE SIZE STATE REMOVABLE BLOCK 0x0000000000000000-0x0000000c3fffffff 49G online yes 0-48 0x0000000c40000000-0x0000000c7fffffff 1G offline 49 0x0000000c80000000-0x0000000fffffffff 14G online yes 50-63 0x0000001000000000-0x00000013ffffffff 16G offline 64-79 s390/mm: Found insecure W+X mapping at address 0xc40000000 WARNING: CPU: 14 PID: 1 at arch/s390/mm/dump_pagetables.c:142 note_page+0x2cc/0x2d8 Map only online memory ranges which fit within identity mapping limit. Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-31s390/decompressor: specify __decompress() buf len to avoid overflowVasily Gorbik
Historically calls to __decompress() didn't specify "out_len" parameter on many architectures including s390, expecting that no writes beyond uncompressed kernel image are performed. This has changed since commit 2aa14b1ab2c4 ("zstd: import usptream v1.5.2") which includes zstd library commit 6a7ede3dfccb ("Reduce size of dctx by reutilizing dst buffer (#2751)"). Now zstd decompression code might store literal buffer in the unwritten portion of the destination buffer. Since "out_len" is not set, it is considered to be unlimited and hence free to use for optimization needs. On s390 this might corrupt initrd or ipl report which are often placed right after the decompressor buffer. Luckily the size of uncompressed kernel image is already known to the decompressor, so to avoid the problem simply specify it in the "out_len" parameter. Link: https://github.com/facebook/zstd/commit/6a7ede3dfccb Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Tested-by: Alexander Egorenkov <egorenar@linux.ibm.com> Link: https://lore.kernel.org/r/patch-1.thread-41c676.git-41c676c2d153.your-ad-here.call-01675030179-ext-9637@work.hours Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-30watchdog: diag288_wdt: fix __diag288() inline assemblyAlexander Egorenkov
The DIAG 288 statement consumes an EBCDIC string the address of which is passed in a register. Use a "memory" clobber to tell the compiler that memory is accessed within the inline assembly. Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>