Unnamed repository; edit this file 'description' to name the repository. https://git.kobert.dev/pm24.git/atom?h=master 2024-11-26T10:06:04Z 2024-11-26T10:06:04Z Huacai Chen chenhuacai@loongson.cn 2024-11-22T07:47:53Z urn:sha1:704f06eeff65f898364981e6803e587cd941a3ed LoongArch has supported PREEMPT_RT now. It uses GENERIC_ENTRY, so just add the TIF bit (TIF_NEED_RESCHED_LAZY) related definitions and select the Kconfig symbol (ARCH_HAS_PREEMPT_LAZY) is enough to make it go. Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 2024-11-26T10:06:04Z Huacai Chen chenhuacai@loongson.cn 2024-11-22T07:47:53Z urn:sha1:be2ea982bb83a34003909bdfcac1d107339f5dcf It is really time. LoongArch has all the required architecture related changes, that have been identified over time, in order to enable PREEMPT_RT. With the recent printk changes, the last known road block has been addressed. Allow to enable PREEMPT_RT on LoongArch. Below are the latency data from cyclictest on a 4-core Loongson-3A5000 machine, with a "make -j8" kernel building workload in the background. 1. PREEMPT kernel with default configuration: ./cyclictest -a -t -m -i200 -d0 -p99 policy: fifo: loadavg: 8.78 8.96 8.64 10/296 64800 T: 0 ( 4592) P:99 I:200 C:14838617 Min: 3 Act: 6 Avg: 8 Max: 844 T: 1 ( 4593) P:99 I:200 C:14838765 Min: 3 Act: 9 Avg: 8 Max: 909 T: 2 ( 4594) P:99 I:200 C:14838510 Min: 3 Act: 7 Avg: 8 Max: 832 T: 3 ( 4595) P:99 I:200 C:14838631 Min: 3 Act: 8 Avg: 8 Max: 931 2. PREEMPT_RT kernel with default configuration: ./cyclictest -a -t -m -i200 -d0 -p99 policy: fifo: loadavg: 10.38 10.47 10.35 9/336 77788 T: 0 ( 3941) P:99 I:200 C:19439626 Min: 3 Act: 12 Avg: 8 Max: 227 T: 1 ( 3942) P:99 I:200 C:19439624 Min: 2 Act: 11 Avg: 8 Max: 184 T: 2 ( 3943) P:99 I:200 C:19439623 Min: 3 Act: 4 Avg: 7 Max: 223 T: 3 ( 3944) P:99 I:200 C:19439623 Min: 2 Act: 10 Avg: 7 Max: 226 3. PREEMPT_RT kernel with tuned configuration: ./cyclictest -a -t -m -i200 -d0 -p99 policy: fifo: loadavg: 10.52 10.66 10.62 12/334 109397 T: 0 ( 4765) P:99 I:200 C:29335186 Min: 3 Act: 6 Avg: 8 Max: 62 T: 1 ( 4766) P:99 I:200 C:29335185 Min: 3 Act: 10 Avg: 8 Max: 52 T: 2 ( 4767) P:99 I:200 C:29335184 Min: 3 Act: 8 Avg: 8 Max: 64 T: 3 ( 4768) P:99 I:200 C:29335183 Min: 3 Act: 12 Avg: 8 Max: 53 Main instruments of tuned configuration include: Disable the boot rom space in BIOS, in order to avoid kernel's speculative access to low- speed memory (i.e. boot rom space); Disable CPUFreq scaling; Disable RTC synchronization in the ntpd/chronyd service (also avoid other RTC accesses when running low-latency workloads). Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 2024-11-26T10:06:04Z Huacai Chen chenhuacai@loongson.cn 2024-11-22T07:47:53Z urn:sha1:826d2af6949f9c48fb5a249be0645e4b48b01a53 Move POSIX CPU timer expiry and signal delivery into task context to allow PREEMPT_RT setups to coexist with KVM. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 2024-11-15T06:43:48Z Dave Vasilevsky dave@vasilevsky.ca 2024-09-17T16:37:20Z urn:sha1:31daa34315d45d3fe77f2158d889d523d78852ea Fixes boot failures on 6.9 on PPC_BOOK3S_32 machines using Open Firmware. On these machines, the kernel refuses to boot from non-zero PHYSICAL_START, which occurs when CRASH_DUMP is on. Since most PPC_BOOK3S_32 machines boot via Open Firmware, it should default to off for them. Users booting via some other mechanism can still turn it on explicitly. Does not change the default on any other architectures for the time being. Link: https://lkml.kernel.org/r/20240917163720.1644584-1-dave@vasilevsky.ca Fixes: 75bc255a7444 ("crash: clean up kdump related config items") Signed-off-by: Dave Vasilevsky <dave@vasilevsky.ca> Reported-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de> Closes: https://lists.debian.org/debian-powerpc/2024/07/msg00001.html Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Acked-by: Baoquan He <bhe@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Reimar Döffinger <Reimar.Doeffinger@gmx.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> 2024-09-27T17:14:35Z Linus Torvalds torvalds@linux-foundation.org 2024-09-27T17:14:35Z urn:sha1:3630400697a3d334a391c1dba1b601d852145f2c Pull LoongArch updates from Huacai Chen: - Fix objtool about do_syscall() and Clang - Enable generic CPU vulnerabilites support - Enable ACPI BGRT handling - Rework CPU feature probe from CPUCFG/IOCSR - Add ARCH_HAS_SET_MEMORY support - Add ARCH_HAS_SET_DIRECT_MAP support - Improve hardware page table walker - Simplify _percpu_read() and _percpu_write() - Add advanced extended IRQ model documentions - Some bug fixes and other small changes * tag 'loongarch-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: Docs/LoongArch: Add advanced extended IRQ model description LoongArch: Remove posix_types.h include from sigcontext.h LoongArch: Fix memleak in pci_acpi_scan_root() LoongArch: Simplify _percpu_read() and _percpu_write() LoongArch: Improve hardware page table walker LoongArch: Add ARCH_HAS_SET_DIRECT_MAP support LoongArch: Add ARCH_HAS_SET_MEMORY support LoongArch: Rework CPU feature probe from CPUCFG/IOCSR LoongArch: Enable ACPI BGRT handling LoongArch: Enable generic CPU vulnerabilites support LoongArch: Remove STACK_FRAME_NON_STANDARD(do_syscall) LoongArch: Set AS_HAS_THIN_ADD_SUB as y if AS_IS_LLVM LoongArch: Enable objtool for Clang objtool: Handle frame pointer related instructions 2024-09-24T07:32:20Z Huacai Chen chenhuacai@loongson.cn 2024-09-24T07:32:20Z urn:sha1:f04de6d8f252ec6434b846895474cc205527b8b8 Add set_direct_map_*() functions for setting the direct map alias for the page to its default permissions and to an invalid state that cannot be cached in a TLB. (See d253ca0c3 ("x86/mm/cpa: Add set_direct_map_*() functions")) Add a similar implementation for LoongArch. This fixes the KFENCE warnings during hibernation: ================================================================== BUG: KFENCE: invalid read in swsusp_save+0x368/0x4d8 Invalid read at 0x00000000f7b89a3c: swsusp_save+0x368/0x4d8 hibernation_snapshot+0x3f0/0x4e0 hibernate+0x20c/0x440 state_store+0x128/0x140 kernfs_fop_write_iter+0x160/0x260 vfs_write+0x2c0/0x520 ksys_write+0x74/0x160 do_syscall+0xb0/0x160 CPU: 0 UID: 0 PID: 812 Comm: bash Tainted: G B 6.11.0-rc1+ #1566 Tainted: [B]=BAD_PAGE Hardware name: Loongson-LS3A5000-7A1000-1w-CRB, BIOS vUDK2018-LoongArch-V2.0.0 10/21/2022 ================================================================== Note: We can only set permissions for KVRANGE/XKVRANGE kernel addresses. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 2024-09-24T07:32:20Z Huacai Chen chenhuacai@loongson.cn 2024-09-24T07:32:20Z urn:sha1:e86935f705fa732d8c7c3ecf0c50ea461ffab76f Add set_memory_ro/rw/x/nx architecture hooks to change the page attribution. Use own set_memory.h rather than generic set_memory.h (i.e. include/asm-generic/set_memory.h), because we want to add other function prototypes here. Note: We can only set attributes for KVRANGE/XKVRANGE kernel addresses. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 2024-09-24T07:31:51Z Tiezhu Yang yangtiezhu@loongson.cn 2024-09-24T07:31:51Z urn:sha1:e8dd556c74325f29597665c2c557a8ea699a0686 Currently, many architectures support generic CPU vulnerabilites, such as x86, arm64 and riscv: commit 61dc0f555b5c ("x86/cpu: Implement CPU vulnerabilites sysfs functions") commit 61ae1321f06c ("arm64: enable generic CPU vulnerabilites support") commit 0e3f3649d44b ("riscv: Enable generic CPU vulnerabilites support") All LoongArch CPUs (since Loongson-3A5000) implement a special mechanism in the processor core to prevent "Meltdown" and "Spectre" attacks, so it can enable generic CPU vulnerabilites support for LoongArch too. Without this patch, there are no user interfaces of vulnerabilities to check on LoongArch. The output of those files reflects the state of the CPUs in the system, the output value "Not affected" means "CPU is not affected by the vulnerability". Before: # cat /sys/devices/system/cpu/vulnerabilities/spec_rstack_overflow cat: /sys/devices/system/cpu/vulnerabilities/spec_rstack_overflow: No such file or directory # cat /sys/devices/system/cpu/vulnerabilities/spec_store_bypass cat: /sys/devices/system/cpu/vulnerabilities/spec_store_bypass: No such file or directory # cat /sys/devices/system/cpu/vulnerabilities/meltdown cat: /sys/devices/system/cpu/vulnerabilities/meltdown: No such file or directory After: # cat /sys/devices/system/cpu/vulnerabilities/spec_rstack_overflow Not affected # cat /sys/devices/system/cpu/vulnerabilities/spec_store_bypass Not affected # cat /sys/devices/system/cpu/vulnerabilities/meltdown Not affected Link: https://www.loongson.cn/EN/news/show?id=633 Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 2024-09-18T13:26:31Z Linus Torvalds torvalds@linux-foundation.org 2024-09-18T13:26:31Z urn:sha1:4a39ac5b7d62679c07a3e3d12b0f6982377d8a7d Pull random number generator updates from Jason Donenfeld: "Originally I'd planned on sending each of the vDSO getrandom() architecture ports to their respective arch trees. But as we started to work on this, we found lots of interesting issues in the shared code and infrastructure, the fixes for which the various archs needed to base their work. So in the end, this turned into a nice collaborative effort fixing up issues and porting to 5 new architectures -- arm64, powerpc64, powerpc32, s390x, and loongarch64 -- with everybody pitching in and commenting on each other's code. It was a fun development cycle. This contains: - Numerous fixups to the vDSO selftest infrastructure, getting it running successfully on more platforms, and fixing bugs in it. - Additions to the vDSO getrandom & chacha selftests. Basically every time manual review unearthed a bug in a revision of an arch patch, or an ambiguity, the tests were augmented. By the time the last arch was submitted for review, s390x, v1 of the series was essentially fine right out of the gate. - Fixes to the the generic C implementation of vDSO getrandom, to build and run successfully on all archs, decoupling it from assumptions we had (unintentionally) made on x86_64 that didn't carry through to the other architectures. - Port of vDSO getrandom to LoongArch64, from Xi Ruoyao and acked by Huacai Chen. - Port of vDSO getrandom to ARM64, from Adhemerval Zanella and acked by Will Deacon. - Port of vDSO getrandom to PowerPC, in both 32-bit and 64-bit varieties, from Christophe Leroy and acked by Michael Ellerman. - Port of vDSO getrandom to S390X from Heiko Carstens, the arch maintainer. While it'd be natural for there to be things to fix up over the course of the development cycle, these patches got a decent amount of review from a fairly diverse crew of folks on the mailing lists, and, for the most part, they've been cooking in linux-next, which has been helpful for ironing out build issues. In terms of architectures, I think that mostly takes care of the important 64-bit archs with hardware still being produced and running production loads in settings where vDSO getrandom is likely to help. Arguably there's still RISC-V left, and we'll see for 6.13 whether they find it useful and submit a port" * tag 'random-6.12-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (47 commits) selftests: vDSO: check cpu caps before running chacha test s390/vdso: Wire up getrandom() vdso implementation s390/vdso: Move vdso symbol handling to separate header file s390/vdso: Allow alternatives in vdso code s390/module: Provide find_section() helper s390/facility: Let test_facility() generate static branch if possible s390/alternatives: Remove ALT_FACILITY_EARLY s390/facility: Disable compile time optimization for decompressor code selftests: vDSO: fix vdso_config for s390 selftests: vDSO: fix ELF hash table entry size for s390x powerpc/vdso: Wire up getrandom() vDSO implementation on VDSO64 powerpc/vdso: Wire up getrandom() vDSO implementation on VDSO32 powerpc/vdso: Refactor CFLAGS for CVDSO build powerpc/vdso32: Add crtsavres mm: Define VM_DROPPABLE for powerpc/32 powerpc/vdso: Fix VDSO data access when running in a non-root time namespace selftests: vDSO: don't include generated headers for chacha test arm64: vDSO: Wire up getrandom() vDSO implementation arm64: alternative: make alternative_has_cap_likely() VDSO compatible selftests: vDSO: also test counter in vdso_test_chacha ... 2024-09-17T14:23:09Z Tiezhu Yang yangtiezhu@loongson.cn 2024-09-17T14:23:09Z urn:sha1:a7e0837724562ea8c1d869dd1a5cb1119ef651c3 When building kernel with "make CC=clang defconfig", LLVM Assembler is used due to LLVM_IAS=0 is not specified, then AS_HAS_THIN_ADD_SUB is not set, thus objtool can not be built after enable it for Clang. config AS_HAS_THIN_ADD_SUB is to check whether -mthin-add-sub option is available to know R_LARCH_{32,64}_PCREL are supported for GNU Assembler, there is no such an option for LLVM Assembler. The minimal version of Clang is 18 for building LoongArch kernel, and Clang >= 17 has already supported R_LARCH_{32,64}_PCREL, that is to say, there is no need to depend on AS_HAS_THIN_ADD_SUB for Clang, so just set AS_HAS_THIN_ADD_SUB as y if AS_IS_LLVM. Fixes: 120dd4118e58 ("LoongArch: Only allow OBJTOOL & ORC unwinder if toolchain supports -mthin-add-sub") Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>