summaryrefslogtreecommitdiff
path: root/arch/s390
AgeCommit message (Collapse)Author
2025-03-10lib/crc: remove unnecessary prompt for CONFIG_CRC4Eric Biggers
All modules that need CONFIG_CRC4 already select it, so there is no need to bother users about the option. Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250304230712.167600-2-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
2025-03-08vdso: Rework struct vdso_time_data and introduce struct vdso_clockAnna-Maria Behnsen
To support multiple PTP clocks, the VDSO data structure needs to be reworked. All clock specific data will end up in struct vdso_clock and in struct vdso_time_data there will be an array of VDSO clocks. Now that all preparatory changes are in place: Split the clock related struct members into a separate struct vdso_clock. Make sure all users are aware, that vdso_time_data is no longer initialized as an array and vdso_clock is now the array inside vdso_data. Remove the vdso_clock define, which mapped it to vdso_time_data for the transition. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-19-c1b5c69a166f@linutronix.de
2025-03-07Merge tag 's390-6.14-6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 fixes from Vasily Gorbik: - Fix return address recovery of traced function in ftrace to ensure reliable stack unwinding - Fix compiler warnings and runtime crashes of vDSO selftests on s390 by introducing a dedicated GNU hash bucket pointer with correct 32-bit entry size - Fix test_monitor_call() inline asm, which misses CC clobber, by switching to an instruction that doesn't modify CC * tag 's390-6.14-6' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/ftrace: Fix return address recovery of traced function selftests/vDSO: Fix GNU hash table entry size for s390x s390/traps: Fix test_monitor_call() inline assembly
2025-03-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.14-rc6). Conflicts: net/ethtool/cabletest.c 2bcf4772e45a ("net: ethtool: try to protect all callback with netdev instance lock") 637399bf7e77 ("net: ethtool: netlink: Allow NULL nlattrs when getting a phy_device") No Adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-04s390/atomic_ops: Let __atomic_add_const() variants always return voidHeiko Carstens
Depending on MARCH_HAS_Z196_FEATURES __atomic_add_const() returns void or the previous value before the atomic variant. Make sure that for both cases void is returned so potential incorrect usage results in both cases in a compile error. Reviewed-by: Juergen Christ <jchrist@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/traps: Change stack overflow messageSven Schnelle
When the kernel stack pointer is pointing to invalid memory, a 'Kernel stack overflow' message is printed, which is misleading. Change the message to actually say that the stack pointer is invalid instead. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/traps: Cleanup coding styleHeiko Carstens
Just some trivial whitespace and coding style changes. 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>
2025-03-04s390/traps: Get rid of superfluous cpu_has_vx() checkHeiko Carstens
If the vector facility is installed cpu_has_vx() is always true, if it is not installed the result is always false, and no vector exception can happen. Therefore remove the superfluous check. 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>
2025-03-04s390/traps: Use pr_emerg() instead of printk()Heiko Carstens
Use pr_emerg() instead of printk() in case of a stack overflow, providing the emergency printk level. Also slightly adjust the printed text for pr_emerg() and panic(). 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>
2025-03-04s390/traps: Cleanup get_user() handling in illegal_op()Heiko Carstens
The usage of get_user() in illegal_op() is quite unusual. Make the code more readable and get rid of unnecessary casts. The generated code is identical before/after this change. 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>
2025-03-04s390/boot: Convert __diag308() to extableHeiko Carstens
Shorten __diag308() and use regular EX_TABLE program check handling. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/boot: Convert detect_diag9c() to extableHeiko Carstens
Shorten detect_diag9c() and use regular EX_TABLE program check handling. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/boot: Convert diag500_storage_limit() to extableHeiko Carstens
Shorten diag500_storage_limit() and use regular EX_TABLE program check handling. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/boot: Convert tprot() to extableHeiko Carstens
Shorten tprot() and use regular EX_TABLE program check handling. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/boot: Convert __diag260() to extableHeiko Carstens
Shorten __diag260() and use regular EX_TABLE program check handling. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/boot: Convert cmma_test_essa() to extableHeiko Carstens
Shorten cmma_test_essa() and use regular EX_TABLE program check handling. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/boot: Add exception table supportHeiko Carstens
The early boot code contains various open-coded inline assemblies with exception handling. In order to handle possible exceptions each of them changes the program check new psw, and restores it. In order to simplify the various inline assemblies add simple exception table support: the program check handler is called with a fully populated pt_regs on the stack and may change the psw and register members. When the program check handler returns the psw and registers from pt_regs will be used to continue execution. The program check handler searches the exception table for an entry which matches the address of the program check. If such an entry is found the psw address within pt_regs on the stack is replaced with a fixup address, and execution continues at the new address. If no entry is found the psw is changed to a disabled wait psw and execution stops. Before entering the C part of the program check handler the address of the program check new psw is replaced to a minimalistic handler. This is supposed to help against program check loops. If an exception happens while in program check processing the register contents of the original exception are restored and a disabled wait psw is loaded. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/boot: Pass pt_regs to program check handlerHeiko Carstens
Setup a pt_regs structure on the stack, poplulate it in low level assembler code, and pass it to print_pgm_check_info(). This way there is no need to access then lowcore from print_pgm_check_info() anymore, and the function looks like a normal program check handler function. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/asm-offsets: Rename __LC_PGM_INT_CODEHeiko Carstens
Avoid confusion and rename __LC_PGM_INT_CODE since it correlates to the pgm_code member of struct lowcore, and not the pgm_int_code member. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390: Use system header file variant of include directiveHeiko Carstens
A few include directives use the local search variant even though the files to be included aren't local. Therefore use the normal system header file variant of the include directive. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/mm: Simplify gap clamping in mmap_base() using clamp()Qasim Ijaz
mmap_base() has logic to ensure that the variable "gap" stays within the range defined by "gap_min" and "gap_max". Replace this with the clamp() macro to shorten and simplify code. Signed-off-by: Qasim Ijaz <qasdev00@gmail.com> Link: https://lore.kernel.org/r/20250204162508.12335-1-qasdev00@gmail.com Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> [gor@linux.ibm.com: also remove the gap_min and gap_max variables] Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/alternatives: Add debug functionalityHeiko Carstens
Similar to x86 and loongarch add a "debug-alternative" command line parameter, which allows for alternative debugging. The parameter itself comes with architecture specific semantics: "debug-alternative" -> print debug message for every single alternative "debug-alternative=0;2" -> print debug message for all alternatives with type 0 and 2 "debug-alternative=0:0-7" -> print debug message for all alternatives with type 0 which have a facility number within the range of 0-7 "debug-alternative=0:!8;1" -> print debug message for all alternatives with type 0, for all facility numbers, except facility 8, and in addition print all alternatives with type 1 A defconfig build currently results in a kernel with more than 20.000 alternatives, where the majority is for the niai alternative (spinlocks), and the relocated lowcore alternative. The following kernel command like options limit alternative debug output, and enable dynamic debug messages: debug-alternative=0:!49;1:!0 earlyprintk bootdebug ignore_loglevel loglevel=8 dyndbg="file alternative.c +p" This results in output like this: alt: [0/ 11] 0000021b9ce8680c: c0f400000089 -> c00400000000 alt: [0/ 64] 0000021b9ce87e60: c0f400000043 -> c00400000000 alt: [0/133] 0000021b9ce88c56: c0f400000027 -> c00400000000 alt: [0/ 74] 0000021b9ce89410: c0f40000002a -> c00400000000 alt: [0/ 40] 0000021b9dc3720a: 47000000 -> b280d398 alt: [0/193] 0000021b9dc37306: 47000000 -> b201d2b0 alt: [0/193] 0000021b9dc37354: c00400000000 -> d20720c0d2b0 alt: [1/ 5] 0000038d720d7bf2: c0f400000016 -> c00400000000 With [<alternative type>/<alternative data>] <address> oldcode -> newcode Alternative data depends on the alternative type: for type 0 (ALT_TYPE_FACILITY) data is the facility. For type 1 (ALT_TYPE_FEATURE) data is the corresponding machine feature. Acked-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/setup: Add decompressor_handled_param() wrapperHeiko Carstens
Make decompressor_handled_param() a wrapper for __decompressor_handled_param(). __decompressor_handled_param() now takes two parameters: a function name and a parameter name, which do not necessarily match. This allows to use characters like "-", which are not allowed in function names, for command line parameters which are handled by the decompressor and should be ignored by the kernel. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/bear: Convert cpu_has_bear() to cpu feature functionHeiko Carstens
Get rid of the cpu_has_bear jump label and convert cpu_has_bear() to a cpu feature function using test_facility() and with that use a static branch. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/vx: Convert cpu_has_vx() to cpu feature functionHeiko Carstens
Instead of having a private cpu_has_vx() implementation use the new common cpu feature method. Move the facility detection to the decompressor so it matches all other cpu features. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390: Convert MACHINE_IS_[LPAR|VM|KVM], etc, machine_is_[lpar|vm|kvm]()Heiko Carstens
Move machine type detection to the decompressor and use static branches to implement and use machine_is_[lpar|vm|kvm]() instead of a runtime check via MACHINE_IS_[LPAR|VM|KVM]. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/sysinfo: Move stsi() to header fileHeiko Carstens
Move stsi() inline assembly to header file so it is possible to use it also for the decompressor. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/sysinfo: Cleanup stsi() inline assemblyHeiko Carstens
Merge stsi() and __stsi() and cleanup the inline assembly. This involves making use of the flag output constraint. Semantically the result is identical to before. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/sysinfo: Remove exception handling from __stsi()Heiko Carstens
The exception handling for __stsi() was added in 2001 when it still was possible to run Linux on systems without LPAR hypervisor, and therefore without an stsi instruction. Given that this is not supported anymore remove the exception handling from the __stsi() inline assembly. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/diag: Convert MACHINE_HAS_DIAG9C to machine_has_diag9c()Heiko Carstens
Use static branch(es) to implement and use machine_has_diag9c() instead of a runtime check via MACHINE_HAS_DIAG9C. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/kvm: Convert MACHINE_HAS_ESOP to machine_has_esop()Heiko Carstens
Use static branch(es) to implement and use machine_has_esop() instead of a runtime check via MACHINE_HAS_ESOP. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/tx: Convert MACHINE_HAS_TE to machine_has_tx()Heiko Carstens
Use static branch(es) to implement and use machine_has_tx() instead of a runtime check with MACHINE_HAS_TE. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/tlb: Convert MACHINE_HAS_TLB_GUEST to machine_has_tlb_guest()Heiko Carstens
Use static branch(es) to implement and use machine_has_tlb_guest() instead of a runtime check via MACHINE_HAS_TLB_GUEST. Also add sclp_early_detect_machine_features() in order to allow for feature detection from the decompressor. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/time: Convert MACHINE_HAS_SCC to machine_has_scc()Heiko Carstens
Use static branch(es) to implement and use machine_has_scc() instead of a runtime check via MACHINE_HAS_SCC. This comes with a cleanup of early time initialization: the initial tod_clock_base value is now passed via the bootdata mechanism, instead of using absolute lowcore as transport vehicle from the decompressor to the kernel. Also the early tod clock initialization is moved to the decompressor which allows to use a static branch with machine_has_scc() within the kernel. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/pci: Get rid of MACHINE_HAS_PCI_MIOHeiko Carstens
Remove MACHINE_FLAG_PCI_MIO/MACHINE_HAS_PCI_MIO and implement the identical functionality with set_machine_feature(), clear_machine_feature() and test_machine_feature(). Acked-by: Niklas Schnelle <schnelle@linux.ibm.com> Tested-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/lowcore: Convert relocated lowcore alternative to machine featureHeiko Carstens
Convert the explicit relocated lowcore alternative type to a more generic machine feature. This only reduces the number of alternative types, but has no impact on code generation. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390: Static branches for machine features infrastructureHeiko Carstens
Provide infrastructure which allows to generate machine_has_<feature>() functions, which are replacing the existing MACHINE_HAS_<feature> macros. Such function usages generate a static branch depending on <feature>. The static branch is patched using an alternative. Each <feature> correlates with a bit set in the machine_features bit field. If the corresponding bit is set, the branch will be patched. In order to have any effect on branch patching feature bits must be set with set_machine_features() in the decompressor before alternatives patching of the kernel image. It is possible to use clear_machine_feature() and test_machine_feature() for machine features which cannot be completely detected within the decompressor, e.g. if common code command line parameters allow to enable or disable certain features. In such cases test_machine_feature() instead of machine_has_feature() must be used within the kernel. This results in a runtime check and not a static branch. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_IDTE to cpu_has_idte()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_EDAT2 to cpu_has_edat2()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_EDAT1 to cpu_has_edat1()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_TOPOLOGY to cpu_has_topology()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_TLB_LC to cpu_has_tlb_lc()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_NX to cpu_has_nx()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_GS to cpu_has_gs()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_RDP to cpu_has_rdp()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/cpufeature: Convert MACHINE_HAS_SEQ_INSN to cpu_has_seq_insn()Heiko Carstens
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/uaccess: Inline __clear_user()Heiko Carstens
Rework __clear_user() similar to raw_copy_from_user() / raw_copy_to_user() and inline the function saving the overhead of branches. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/uaccess: Optimize raw_copy_from_user() / raw_copy_to_user() for ↵Heiko Carstens
constant sizes Avoid that the compiler generates an mvcos loop for constant sizes smaller than 4096 bytes. The mvcos instruction copies between zero and 4096 bytes (effective length) with one operation. Therefore it is not necessary to implement a loop for sizes smaller or equal to 4096 bytes. This reduces the kernel text size by ~50kb (defconfig, gcc 14.2.0): add/remove: 4/5 grow/shrink: 6/471 up/down: 2294/-51700 (-49406) Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/uaccess: Define INLINE_COPY_FROM_USER and INLINE_COPY_TO_USERHeiko Carstens
Inline copy_from_user() and copy_to_user(). With the shortened inline assemblies of raw_copy_to_user() and raw_copy_from_user() the additional kernel text size is acceptable, considering that this avoids function calls on hot paths. This increases the kernel text size by ~90kb (defconfig, gcc 14.2.0): add/remove: 13/4 grow/shrink: 650/14 up/down: 93484/-3254 (90230) Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04s390/uaccess: Separate key uaccess functionsHeiko Carstens
Implement separate raw_copy_to_user_key() and raw_copy_from_user_key() functions, which allows to remove the open-coded operand access control handling from the normal raw_copy_to_user() / raw_copy_from_user() functions - they are simplified to use immediate instructions to load hard-coded operand access control values into register zero, which saves one instruction. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
generated by cgit (git 2.34.1) at 2025-07-18 02:51:10 +0000