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2021-01-06mips: kill unused definitions in binfmt_elf[on]32.cAl Viro2-36/+0
elf_caddr_t: unused since 2002 jiffies_to_timeval: unused since 2015 TASK_SIZE: used only downstream of SET_PERSONALITY2(), and after that point the normal definition results in TASK_SIZE32 just fine. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-01-06mips binfmt_elf*32.c: use elfcore-compat.hAl Viro2-65/+8
... rather than duplicating declarations from it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-01-06Merge remote-tracking branch 'mips/mips-fixes' into work.elf-compatAl Viro2-0/+14
backmerge of mips compat coredump fix
2021-01-06elf_prstatus: collect the common part (everything before pr_reg) into a structAl Viro2-2/+11
Preparations to doing i386 compat elf_prstatus sanely - rather than duplicating the beginning of compat_elf_prstatus, take these fields into a separate structure (compat_elf_prstatus_common), so that it could be reused. Due to the incestous relationship between binfmt_elf.c and compat_binfmt_elf.c we need the same shape change done to native struct elf_prstatus, gathering the fields prior to pr_reg into a new structure (struct elf_prstatus_common). Fortunately, offset of pr_reg is always a multiple of 16 with no padding right before it, so it's possible to turn all the stuff prior to it into a single member without disturbing the layout. [build fix from Geert Uytterhoeven folded in] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-01-04MIPS: Kill RM7K & RM9K IRQ CodeJiaxun Yang2-46/+0
RM7000 IRQ driver never got really used by any of the platform, and rm9k_cpu_irq_init only exist in a header. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2021-01-04MIPS: perf: Add support for OCTEON III perf events.Jia Qingtong1-9/+13
According to Hardware Reference Manual, OCTEON III are mostly same as previous OCTEON models. So just enable them and extend supported event code. 0x3e and 0x3f still reserved. Signed-off-by: Jia Qingtong <jiaqingtong97@163.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2021-01-04MIPS: cacheinfo: Add missing VCacheJiaxun Yang1-8/+26
Victim Cache is defined by Loongson as per-core unified private Cache. Add this into cacheinfo and make cache levels selfincrement instead of hardcode levels. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Reviewed-by: Tiezhu Yang <yangtiezhu@loongson.cn> Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-12-28MIPS: Fix malformed NT_FILE and NT_SIGINFO in 32bit coredumpsAl Viro2-0/+14
Patches that introduced NT_FILE and NT_SIGINFO notes back in 2012 had taken care of native (fs/binfmt_elf.c) and compat (fs/compat_binfmt_elf.c) coredumps; unfortunately, compat on mips (which does not go through the usual compat_binfmt_elf.c) had not been noticed. As the result, both N32 and O32 coredumps on 64bit mips kernels have those sections malformed enough to confuse the living hell out of all gdb and readelf versions (up to and including the tip of binutils-gdb.git). Longer term solution is to make both O32 and N32 compat use the regular compat_binfmt_elf.c, but that's too much for backports. The minimal solution is to do in arch/mips/kernel/binfmt_elf[on]32.c the same thing those patches have done in fs/compat_binfmt_elf.c Cc: stable@kernel.org # v3.7+ Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-12-28MIPS: No need to check CPU 0 in cps_cpu_disable()Tiezhu Yang1-3/+0
After commit 9cce844abf07 ("MIPS: CPU#0 is not hotpluggable"), c->hotpluggable is 0 for CPU 0 and it will not generate a control file in sysfs for this CPU: [root@linux loongson]# cat /sys/devices/system/cpu/cpu0/online cat: /sys/devices/system/cpu/cpu0/online: No such file or directory [root@linux loongson]# echo 0 > /sys/devices/system/cpu/cpu0/online bash: /sys/devices/system/cpu/cpu0/online: Permission denied So no need to check CPU 0 in cps_cpu_disable(), just remove it. Reported-by: liwei (GF) <liwei391@huawei.com> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-12-28mips: pci: convert comma to semicolonZheng Yongjun1-2/+2
Replace a comma between expression statements by a semicolon. Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-12-28mips: kernel: convert comma to semicolonZheng Yongjun2-3/+3
Replace a comma between expression statements by a semicolon. Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-12-20epoll: fix compat syscall wire up of epoll_pwait2Heiko Carstens1-1/+1
Commit b0a0c2615f6f ("epoll: wire up syscall epoll_pwait2") wired up the 64 bit syscall instead of the compat variant in a couple of places. Fixes: b0a0c2615f6f ("epoll: wire up syscall epoll_pwait2") Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Willem de Bruijn <willemb@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-19epoll: wire up syscall epoll_pwait2Willem de Bruijn3-0/+3
Split off from prev patch in the series that implements the syscall. Link: https://lkml.kernel.org/r/20201121144401.3727659-4-willemdebruijn.kernel@gmail.com Signed-off-by: Willem de Bruijn <willemb@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-16Merge tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+1
Pull TIF_NOTIFY_SIGNAL updates from Jens Axboe: "This sits on top of of the core entry/exit and x86 entry branch from the tip tree, which contains the generic and x86 parts of this work. Here we convert the rest of the archs to support TIF_NOTIFY_SIGNAL. With that done, we can get rid of JOBCTL_TASK_WORK from task_work and signal.c, and also remove a deadlock work-around in io_uring around knowing that signal based task_work waking is invoked with the sighand wait queue head lock. The motivation for this work is to decouple signal notify based task_work, of which io_uring is a heavy user of, from sighand. The sighand lock becomes a huge contention point, particularly for threaded workloads where it's shared between threads. Even outside of threaded applications it's slower than it needs to be. Roman Gershman <romger@amazon.com> reported that his networked workload dropped from 1.6M QPS at 80% CPU to 1.0M QPS at 100% CPU after io_uring was changed to use TIF_NOTIFY_SIGNAL. The time was all spent hammering on the sighand lock, showing 57% of the CPU time there [1]. There are further cleanups possible on top of this. One example is TIF_PATCH_PENDING, where a patch already exists to use TIF_NOTIFY_SIGNAL instead. Hopefully this will also lead to more consolidation, but the work stands on its own as well" [1] https://github.com/axboe/liburing/issues/215 * tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block: (28 commits) io_uring: remove 'twa_signal_ok' deadlock work-around kernel: remove checking for TIF_NOTIFY_SIGNAL signal: kill JOBCTL_TASK_WORK io_uring: JOBCTL_TASK_WORK is no longer used by task_work task_work: remove legacy TWA_SIGNAL path sparc: add support for TIF_NOTIFY_SIGNAL riscv: add support for TIF_NOTIFY_SIGNAL nds32: add support for TIF_NOTIFY_SIGNAL ia64: add support for TIF_NOTIFY_SIGNAL h8300: add support for TIF_NOTIFY_SIGNAL c6x: add support for TIF_NOTIFY_SIGNAL alpha: add support for TIF_NOTIFY_SIGNAL xtensa: add support for TIF_NOTIFY_SIGNAL arm: add support for TIF_NOTIFY_SIGNAL microblaze: add support for TIF_NOTIFY_SIGNAL hexagon: add support for TIF_NOTIFY_SIGNAL csky: add support for TIF_NOTIFY_SIGNAL openrisc: add support for TIF_NOTIFY_SIGNAL sh: add support for TIF_NOTIFY_SIGNAL um: add support for TIF_NOTIFY_SIGNAL ...
2020-12-16Merge tag 'mips_5.11' of ↵Linus Torvalds6-12/+19
git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux Pull MIPS updates from Thomas Bogendoerfer: - enable GCOV - rework setup of protection map - add support for more MSCC platforms - add sysfs boardinfo for Loongson64 - enable KASLR for Loogson64 - add reset controller for BCM63xx - cleanups and fixes * tag 'mips_5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (70 commits) mips: fix Section mismatch in reference MAINTAINERS: Add linux-mips mailing list to JZ47xx entries MAINTAINERS: Remove JZ4780 DMA driver entry MAINTAINERS: chenhc@lemote.com -> chenhuacai@kernel.org MIPS: Octeon: irq: Alloc desc before configuring IRQ MIPS: mm: Add back define for PAGE_SHARED MIPS: Select ARCH_KEEP_MEMBLOCK if DEBUG_KERNEL to enable sysfs memblock debug mips: lib: uncached: fix non-standard usage of variable 'sp' MIPS: DTS: img: Fix schema warnings for pwm-leds MIPS: KASLR: Avoid endless loop in sync_icache if synci_step is zero MIPS: Move memblock_dump_all() to the end of setup_arch() MIPS: SMP-CPS: Add support for irq migration when CPU offline MIPS: OCTEON: Don't add kernel sections into memblock allocator MIPS: Don't round up kernel sections size for memblock_add() MIPS: Enable GCOV MIPS: configs: drop unused BACKLIGHT_GENERIC option MIPS: Loongson64: Fix up reserving kernel memory range MIPS: mm: Remove unused is_aligned_hugepage_range MIPS: No need to check CPU 0 in {loongson3,bmips,octeon}_cpu_disable() mips: cdmm: fix use-after-free in mips_cdmm_bus_discover ...
2020-12-14Merge tag 'sched-core-2020-12-14' of ↵Linus Torvalds2-21/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Thomas Gleixner: - migrate_disable/enable() support which originates from the RT tree and is now a prerequisite for the new preemptible kmap_local() API which aims to replace kmap_atomic(). - A fair amount of topology and NUMA related improvements - Improvements for the frequency invariant calculations - Enhanced robustness for the global CPU priority tracking and decision making - The usual small fixes and enhancements all over the place * tag 'sched-core-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (61 commits) sched/fair: Trivial correction of the newidle_balance() comment sched/fair: Clear SMT siblings after determining the core is not idle sched: Fix kernel-doc markup x86: Print ratio freq_max/freq_base used in frequency invariance calculations x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC x86, sched: Calculate frequency invariance for AMD systems irq_work: Optimize irq_work_single() smp: Cleanup smp_call_function*() irq_work: Cleanup sched: Limit the amount of NUMA imbalance that can exist at fork time sched/numa: Allow a floating imbalance between NUMA nodes sched: Avoid unnecessary calculation of load imbalance at clone time sched/numa: Rename nr_running and break out the magic number sched: Make migrate_disable/enable() independent of RT sched/topology: Condition EAS enablement on FIE support arm64: Rebuild sched domains on invariance status changes sched/topology,schedutil: Wrap sched domains rebuild sched/uclamp: Allow to reset a task uclamp constraint value sched/core: Fix typos in comments Documentation: scheduler: fix information on arch SD flags, sched_domain and sched_debug ...
2020-12-05MIPS: KASLR: Avoid endless loop in sync_icache if synci_step is zeroJinyang He1-1/+1
Most platforms do not need to do synci instruction operations when synci_step is 0. But for example, the synci implementation on Loongson64 platform has some changes. On the one hand, it ensures that the memory access instructions have been completed. On the other hand, it guarantees that all prefetch instructions need to be fetched again. And its address information is useless. Thus, only one synci operation is required when synci_step is 0 on Loongson64 platform. I guess that some other platforms have similar implementations on synci, so add judgment conditions in `while` to ensure that at least all platforms perform synci operations once. For those platforms that do not need synci, they just do one more operation similar to nop. Signed-off-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-12-04MIPS: Move memblock_dump_all() to the end of setup_arch()Tiezhu Yang1-2/+2
In order to get more memblock configuration with memblock=debug in the boot cmdline, move memblock_dump_all() to the end of setup_arch(), this can help us to get dmi_setup() and resource_init() memblock info, at least for now. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-12-04MIPS: SMP-CPS: Add support for irq migration when CPU offlineWei Li1-0/+2
Currently we won't migrate irqs when offline CPUs, which has been implemented on most architectures. That will lead to some devices work incorrectly if the bound cores are offline. While that can be easily supported by enabling GENERIC_IRQ_MIGRATION. But i don't pretty known the reason it was not supported on all MIPS platforms. This patch add the support for irq migration on MIPS CPS platform, and it's tested on the interAptiv processor. Signed-off-by: Wei Li <liwei391@huawei.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-12-04MIPS: Don't round up kernel sections size for memblock_add()Alexander Sverdlin1-2/+2
Linux doesn't own the memory immediately after the kernel image. On Octeon bootloader places a shared structure right close after the kernel _end, refer to "struct cvmx_bootinfo *octeon_bootinfo" in cavium-octeon/setup.c. If check_kernel_sections_mem() rounds the PFNs up, first memblock_alloc() inside early_init_dt_alloc_memory_arch() <= device_tree_init() returns memory block overlapping with the above octeon_bootinfo structure, which is being overwritten afterwards. Fixes: a94e4f24ec83 ("MIPS: init: Drop boot_mem_map") Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-11-29Merge tag 'locking-urgent-2020-11-29' of ↵Linus Torvalds1-6/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "Two more places which invoke tracing from RCU disabled regions in the idle path. Similar to the entry path the low level idle functions have to be non-instrumentable" * tag 'locking-urgent-2020-11-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: intel_idle: Fix intel_idle() vs tracing sched/idle: Fix arch_cpu_idle() vs tracing
2020-11-27Merge branch 'linus' into sched/core, to resolve semantic conflictIngo Molnar1-3/+3
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-11-27MIPS: No need to check CPU 0 in {loongson3,bmips,octeon}_cpu_disable()Tiezhu Yang1-3/+0
After commit 9cce844abf07 ("MIPS: CPU#0 is not hotpluggable"), c->hotpluggable is 0 for CPU 0 and it will not generate a control file in sysfs for this CPU: [root@linux loongson]# cat /sys/devices/system/cpu/cpu0/online cat: /sys/devices/system/cpu/cpu0/online: No such file or directory [root@linux loongson]# echo 0 > /sys/devices/system/cpu/cpu0/online bash: /sys/devices/system/cpu/cpu0/online: Permission denied So no need to check CPU 0 in {loongson3,bmips,octeon}_cpu_disable(), just remove them. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-11-27MIPS: Loongson64: Add KASLR supportJinyang He1-0/+7
Provide a weak plat_get_fdt() in relocate.c in case some platform enable USE_OF while plat_get_fdt() is useless. 1MB RELOCATION_TABLE_SIZE is small for Loongson64 because too many instructions should be relocated. 2MB is enough in present. Add KASLR support for Loongson64. KASLR(kernel address space layout randomization) To enable KASLR on Loongson64: First, make loongson3_defconfig. Then, enable CONFIG_RELOCATABLE and CONFIG_RANDOMIZE_BASE. Finally, compile the kernel. To test KASLR on Loongson64: Start machine with KASLR kernel. The first time: # cat /proc/iomem 00200000-0effffff : System RAM 02f30000-03895e9f : Kernel code 03895ea0-03bc7fff : Kernel data 03e30000-04f43f7f : Kernel bss The second time: # cat /proc/iomem 00200000-0effffff : System RAM 022f0000-02c55e9f : Kernel code 02c55ea0-02f87fff : Kernel data 031f0000-04303f7f : Kernel bss We see that code, data and bss sections become randomize. Signed-off-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-11-27MIPS: KASLR: Correct valid bits in apply_r_mips_26_rel()Jinyang He1-2/+2
Apply_r_mips_26_rel() relocates instructions like j, jal and etc. These instructions consist of 6bits function field and 26bits address field. The value of target_addr as follows, ================================================================= | high 4bits | low 28bits | ================================================================= |the high 4bits of this PC | the low 26bits of instructions << 2| ================================================================= Thus, loc_orig and log_new both need high 4bits rather than high 6bits. Signed-off-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-11-24smp: Cleanup smp_call_function*()Peter Zijlstra2-21/+9
Get rid of the __call_single_node union and cleanup the API a little to avoid external code relying on the structure layout as much. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
2020-11-24sched/idle: Fix arch_cpu_idle() vs tracingPeter Zijlstra1-6/+6
We call arch_cpu_idle() with RCU disabled, but then use local_irq_{en,dis}able(), which invokes tracing, which relies on RCU. Switch all arch_cpu_idle() implementations to use raw_local_irq_{en,dis}able() and carefully manage the lockdep,rcu,tracing state like we do in entry. (XXX: we really should change arch_cpu_idle() to not return with interrupts enabled) Reported-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
2020-11-19MIPS: vdso: Use vma page protection for remappingThomas Bogendoerfer1-2/+2
MIPS protection bits are setup during runtime so using defines like PAGE_READONLY ignores these runtime changes. To fix this we simply use the page protection of the setup vma. Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-11-17Merge tag 'mips_fixes_5.10_1' into mips-nextThomas Bogendoerfer1-3/+3
Pull in mips-fixes to get memblock fix. - fix bug preventing booting on several platforms - fix for build error, when modules need has_transparent_hugepage - fix for memleak in alchemy clk setup Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-11-17MIPS: kernel: Fix for_each_memblock conversionThomas Bogendoerfer1-3/+3
The loop over all memblocks works with PFNs and not physical addresses, so we need for_each_mem_pfn_range(). Fixes: b10d6bca8720 ("arch, drivers: replace for_each_membock() with for_each_mem_range()") Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
2020-11-09mips: add support for TIF_NOTIFY_SIGNALJens Axboe1-1/+1
Wire up TIF_NOTIFY_SIGNAL handling for mips. Cc: linux-mips@vger.kernel.org Acked-By: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-11-06mips: cm: add missing iounmap() on error in mips_cm_probe()Qinglang Miao1-0/+1
Add the missing iounmap() of iounmap(mips_gcr_base) before return from mips_cm_probe() in the error handling case. Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-10-25treewide: Convert macro and uses of __section(foo) to __section("foo")Joe Perches1-1/+1
Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-23Merge tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+0
Pull arch task_work cleanups from Jens Axboe: "Two cleanups that don't fit other categories: - Finally get the task_work_add() cleanup done properly, so we don't have random 0/1/false/true/TWA_SIGNAL confusing use cases. Updates all callers, and also fixes up the documentation for task_work_add(). - While working on some TIF related changes for 5.11, this TIF_NOTIFY_RESUME cleanup fell out of that. Remove some arch duplication for how that is handled" * tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-block: task_work: cleanup notification modes tracehook: clear TIF_NOTIFY_RESUME in tracehook_notify_resume()
2020-10-18mm/madvise: introduce process_madvise() syscall: an external memory hinting APIMinchan Kim3-0/+3
There is usecase that System Management Software(SMS) want to give a memory hint like MADV_[COLD|PAGEEOUT] to other processes and in the case of Android, it is the ActivityManagerService. The information required to make the reclaim decision is not known to the app. Instead, it is known to the centralized userspace daemon(ActivityManagerService), and that daemon must be able to initiate reclaim on its own without any app involvement. To solve the issue, this patch introduces a new syscall process_madvise(2). It uses pidfd of an external process to give the hint. It also supports vector address range because Android app has thousands of vmas due to zygote so it's totally waste of CPU and power if we should call the syscall one by one for each vma.(With testing 2000-vma syscall vs 1-vector syscall, it showed 15% performance improvement. I think it would be bigger in real practice because the testing ran very cache friendly environment). Another potential use case for the vector range is to amortize the cost ofTLB shootdowns for multiple ranges when using MADV_DONTNEED; this could benefit users like TCP receive zerocopy and malloc implementations. In future, we could find more usecases for other advises so let's make it happens as API since we introduce a new syscall at this moment. With that, existing madvise(2) user could replace it with process_madvise(2) with their own pid if they want to have batch address ranges support feature. ince it could affect other process's address range, only privileged process(PTRACE_MODE_ATTACH_FSCREDS) or something else(e.g., being the same UID) gives it the right to ptrace the process could use it successfully. The flag argument is reserved for future use if we need to extend the API. I think supporting all hints madvise has/will supported/support to process_madvise is rather risky. Because we are not sure all hints make sense from external process and implementation for the hint may rely on the caller being in the current context so it could be error-prone. Thus, I just limited hints as MADV_[COLD|PAGEOUT] in this patch. If someone want to add other hints, we could hear the usecase and review it for each hint. It's safer for maintenance rather than introducing a buggy syscall but hard to fix it later. So finally, the API is as follows, ssize_t process_madvise(int pidfd, const struct iovec *iovec, unsigned long vlen, int advice, unsigned int flags); DESCRIPTION The process_madvise() system call is used to give advice or directions to the kernel about the address ranges from external process as well as local process. It provides the advice to address ranges of process described by iovec and vlen. The goal of such advice is to improve system or application performance. The pidfd selects the process referred to by the PID file descriptor specified in pidfd. (See pidofd_open(2) for further information) The pointer iovec points to an array of iovec structures, defined in <sys/uio.h> as: struct iovec { void *iov_base; /* starting address */ size_t iov_len; /* number of bytes to be advised */ }; The iovec describes address ranges beginning at address(iov_base) and with size length of bytes(iov_len). The vlen represents the number of elements in iovec. The advice is indicated in the advice argument, which is one of the following at this moment if the target process specified by pidfd is external. MADV_COLD MADV_PAGEOUT Permission to provide a hint to external process is governed by a ptrace access mode PTRACE_MODE_ATTACH_FSCREDS check; see ptrace(2). The process_madvise supports every advice madvise(2) has if target process is in same thread group with calling process so user could use process_madvise(2) to extend existing madvise(2) to support vector address ranges. RETURN VALUE On success, process_madvise() returns the number of bytes advised. This return value may be less than the total number of requested bytes, if an error occurred. The caller should check return value to determine whether a partial advice occurred. FAQ: Q.1 - Why does any external entity have better knowledge? Quote from Sandeep "For Android, every application (including the special SystemServer) are forked from Zygote. The reason of course is to share as many libraries and classes between the two as possible to benefit from the preloading during boot. After applications start, (almost) all of the APIs end up calling into this SystemServer process over IPC (binder) and back to the application. In a fully running system, the SystemServer monitors every single process periodically to calculate their PSS / RSS and also decides which process is "important" to the user for interactivity. So, because of how these processes start _and_ the fact that the SystemServer is looping to monitor each process, it does tend to *know* which address range of the application is not used / useful. Besides, we can never rely on applications to clean things up themselves. We've had the "hey app1, the system is low on memory, please trim your memory usage down" notifications for a long time[1]. They rely on applications honoring the broadcasts and very few do. So, if we want to avoid the inevitable killing of the application and restarting it, some way to be able to tell the OS about unimportant memory in these applications will be useful. - ssp Q.2 - How to guarantee the race(i.e., object validation) between when giving a hint from an external process and get the hint from the target process? process_madvise operates on the target process's address space as it exists at the instant that process_madvise is called. If the space target process can run between the time the process_madvise process inspects the target process address space and the time that process_madvise is actually called, process_madvise may operate on memory regions that the calling process does not expect. It's the responsibility of the process calling process_madvise to close this race condition. For example, the calling process can suspend the target process with ptrace, SIGSTOP, or the freezer cgroup so that it doesn't have an opportunity to change its own address space before process_madvise is called. Another option is to operate on memory regions that the caller knows a priori will be unchanged in the target process. Yet another option is to accept the race for certain process_madvise calls after reasoning that mistargeting will do no harm. The suggested API itself does not provide synchronization. It also apply other APIs like move_pages, process_vm_write. The race isn't really a problem though. Why is it so wrong to require that callers do their own synchronization in some manner? Nobody objects to write(2) merely because it's possible for two processes to open the same file and clobber each other's writes --- instead, we tell people to use flock or something. Think about mmap. It never guarantees newly allocated address space is still valid when the user tries to access it because other threads could unmap the memory right before. That's where we need synchronization by using other API or design from userside. It shouldn't be part of API itself. If someone needs more fine-grained synchronization rather than process level, there were two ideas suggested - cookie[2] and anon-fd[3]. Both are applicable via using last reserved argument of the API but I don't think it's necessary right now since we have already ways to prevent the race so don't want to add additional complexity with more fine-grained optimization model. To make the API extend, it reserved an unsigned long as last argument so we could support it in future if someone really needs it. Q.3 - Why doesn't ptrace work? Injecting an madvise in the target process using ptrace would not work for us because such injected madvise would have to be executed by the target process, which means that process would have to be runnable and that creates the risk of the abovementioned race and hinting a wrong VMA. Furthermore, we want to act the hint in caller's context, not the callee's, because the callee is usually limited in cpuset/cgroups or even freezed state so they can't act by themselves quick enough, which causes more thrashing/kill. It doesn't work if the target process are ptraced(e.g., strace, debugger, minidump) because a process can have at most one ptracer. [1] https://developer.android.com/topic/performance/memory" [2] process_getinfo for getting the cookie which is updated whenever vma of process address layout are changed - Daniel Colascione - https://lore.kernel.org/lkml/20190520035254.57579-1-minchan@kernel.org/T/#m7694416fd179b2066a2c62b5b139b14e3894e224 [3] anonymous fd which is used for the object(i.e., address range) validation - Michal Hocko - https://lore.kernel.org/lkml/20200120112722.GY18451@dhcp22.suse.cz/ [minchan@kernel.org: fix process_madvise build break for arm64] Link: http://lkml.kernel.org/r/20200303145756.GA219683@google.com [minchan@kernel.org: fix build error for mips of process_madvise] Link: http://lkml.kernel.org/r/20200508052517.GA197378@google.com [akpm@linux-foundation.org: fix patch ordering issue] [akpm@linux-foundation.org: fix arm64 whoops] [minchan@kernel.org: make process_madvise() vlen arg have type size_t, per Florian] [akpm@linux-foundation.org: fix i386 build] [sfr@canb.auug.org.au: fix syscall numbering] Link: https://lkml.kernel.org/r/20200905142639.49fc3f1a@canb.auug.org.au [sfr@canb.auug.org.au: madvise.c needs compat.h] Link: https://lkml.kernel.org/r/20200908204547.285646b4@canb.auug.org.au [minchan@kernel.org: fix mips build] Link: https://lkml.kernel.org/r/20200909173655.GC2435453@google.com [yuehaibing@huawei.com: remove duplicate header which is included twice] Link: https://lkml.kernel.org/r/20200915121550.30584-1-yuehaibing@huawei.com [minchan@kernel.org: do not use helper functions for process_madvise] Link: https://lkml.kernel.org/r/20200921175539.GB387368@google.com [akpm@linux-foundation.org: pidfd_get_pid() gained an argument] [sfr@canb.auug.org.au: fix up for "iov_iter: transparently handle compat iovecs in import_iovec"] Link: https://lkml.kernel.org/r/20200928212542.468e1fef@canb.auug.org.au Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Brian Geffon <bgeffon@google.com> Cc: Christian Brauner <christian@brauner.io> Cc: Daniel Colascione <dancol@google.com> Cc: Jann Horn <jannh@google.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Dias <joaodias@google.com> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oleksandr Natalenko <oleksandr@redhat.com> Cc: Sandeep Patil <sspatil@google.com> Cc: SeongJae Park <sj38.park@gmail.com> Cc: SeongJae Park <sjpark@amazon.de> Cc: Shakeel Butt <shakeelb@google.com> Cc: Sonny Rao <sonnyrao@google.com> Cc: Tim Murray <timmurray@google.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Florian Weimer <fw@deneb.enyo.de> Cc: <linux-man@vger.kernel.org> Link: http://lkml.kernel.org/r/20200302193630.68771-3-minchan@kernel.org Link: http://lkml.kernel.org/r/20200508183320.GA125527@google.com Link: http://lkml.kernel.org/r/20200622192900.22757-4-minchan@kernel.org Link: https://lkml.kernel.org/r/20200901000633.1920247-4-minchan@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-17tracehook: clear TIF_NOTIFY_RESUME in tracehook_notify_resume()Jens Axboe1-1/+0
All the callers currently do this, clean it up and move the clearing into tracehook_notify_resume() instead. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-16Merge tag 'mips_5.10' of ↵Linus Torvalds15-419/+612
git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux Pull MIPS updates from Thomas Bogendoerfer: - removed support for PNX833x alias NXT_STB22x - included Ingenic SoC support into generic MIPS kernels - added support for new Ingenic SoCs - converted workaround selection to use Kconfig - replaced old boot mem functions by memblock_* - enabled COP2 usage in kernel for Loongson64 to make use of 16byte load/stores possible - cleanups and fixes * tag 'mips_5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (92 commits) MIPS: DEC: Restore bootmem reservation for firmware working memory area MIPS: dec: fix section mismatch bcm963xx_tag.h: fix duplicated word mips: ralink: enable zboot support MIPS: ingenic: Remove CPU_SUPPORTS_HUGEPAGES MIPS: cpu-probe: remove MIPS_CPU_BP_GHIST option bit MIPS: cpu-probe: introduce exclusive R3k CPU probe MIPS: cpu-probe: move fpu probing/handling into its own file MIPS: replace add_memory_region with memblock MIPS: Loongson64: Clean up numa.c MIPS: Loongson64: Select SMP in Kconfig to avoid build error mips: octeon: Add Ubiquiti E200 and E220 boards MIPS: SGI-IP28: disable use of ll/sc in kernel MIPS: tx49xx: move tx4939_add_memory_regions into only user MIPS: pgtable: Remove used PAGE_USERIO define MIPS: alchemy: Share prom_init implementation MIPS: alchemy: Fix build breakage, if TOUCHSCREEN_WM97XX is disabled MIPS: process: include exec.h header in process.c MIPS: process: Add prototype for function arch_dup_task_struct MIPS: idle: Add prototype for function check_wait ...
2020-10-15Merge tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-1/+1
Pull dma-mapping updates from Christoph Hellwig: - rework the non-coherent DMA allocator - move private definitions out of <linux/dma-mapping.h> - lower CMA_ALIGNMENT (Paul Cercueil) - remove the omap1 dma address translation in favor of the common code - make dma-direct aware of multiple dma offset ranges (Jim Quinlan) - support per-node DMA CMA areas (Barry Song) - increase the default seg boundary limit (Nicolin Chen) - misc fixes (Robin Murphy, Thomas Tai, Xu Wang) - various cleanups * tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits) ARM/ixp4xx: add a missing include of dma-map-ops.h dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling dma-direct: factor out a dma_direct_alloc_from_pool helper dma-direct check for highmem pages in dma_direct_alloc_pages dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h> dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma dma-mapping: move dma-debug.h to kernel/dma/ dma-mapping: remove <asm/dma-contiguous.h> dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h> dma-contiguous: remove dma_contiguous_set_default dma-contiguous: remove dev_set_cma_area dma-contiguous: remove dma_declare_contiguous dma-mapping: split <linux/dma-mapping.h> cma: decrease CMA_ALIGNMENT lower limit to 2 firewire-ohci: use dma_alloc_pages dma-iommu: implement ->alloc_noncoherent dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods dma-mapping: add a new dma_alloc_pages API dma-mapping: remove dma_cache_sync 53c700: convert to dma_alloc_noncoherent ...
2020-10-13arch, drivers: replace for_each_membock() with for_each_mem_range()Mike Rapoport1-16/+15
There are several occurrences of the following pattern: for_each_memblock(memory, reg) { start = __pfn_to_phys(memblock_region_memory_base_pfn(reg); end = __pfn_to_phys(memblock_region_memory_end_pfn(reg)); /* do something with start and end */ } Using for_each_mem_range() iterator is more appropriate in such cases and allows simpler and cleaner code. [akpm@linux-foundation.org: fix arch/arm/mm/pmsa-v7.c build] [rppt@linux.ibm.com: mips: fix cavium-octeon build caused by memblock refactoring] Link: http://lkml.kernel.org/r/20200827124549.GD167163@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Axtens <dja@axtens.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Emil Renner Berthing <kernel@esmil.dk> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: https://lkml.kernel.org/r/20200818151634.14343-13-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-12Merge branch 'compat.mount' of ↵Linus Torvalds2-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull compat mount cleanups from Al Viro: "The last remnants of mount(2) compat buried by Christoph. Buried into NFS, that is. Generally I'm less enthusiastic about "let's use in_compat_syscall() deep in call chain" kind of approach than Christoph seems to be, but in this case it's warranted - that had been an NFS-specific wart, hopefully not to be repeated in any other filesystems (read: any new filesystem introducing non-text mount options will get NAKed even if it doesn't mess the layout up). IOW, not worth trying to grow an infrastructure that would avoid that use of in_compat_syscall()..." * 'compat.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: remove compat_sys_mount fs,nfs: lift compat nfs4 mount data handling into the nfs code nfs: simplify nfs4_parse_monolithic
2020-10-12Merge branch 'work.iov_iter' of ↵Linus Torvalds2-10/+10
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull compat iovec cleanups from Al Viro: "Christoph's series around import_iovec() and compat variant thereof" * 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: security/keys: remove compat_keyctl_instantiate_key_iov mm: remove compat_process_vm_{readv,writev} fs: remove compat_sys_vmsplice fs: remove the compat readv/writev syscalls fs: remove various compat readv/writev helpers iov_iter: transparently handle compat iovecs in import_iovec iov_iter: refactor rw_copy_check_uvector and import_iovec iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c compat.h: fix a spelling error in <linux/compat.h>
2020-10-12Merge tag 'perf-kprobes-2020-10-12' of ↵Linus Torvalds1-51/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf/kprobes updates from Ingo Molnar: "This prepares to unify the kretprobe trampoline handler and make kretprobe lockless (those patches are still work in progress)" * tag 'perf-kprobes-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kprobes: Fix to check probe enabled before disarm_kprobe_ftrace() kprobes: Make local functions static kprobes: Free kretprobe_instance with RCU callback kprobes: Remove NMI context check sparc: kprobes: Use generic kretprobe trampoline handler sh: kprobes: Use generic kretprobe trampoline handler s390: kprobes: Use generic kretprobe trampoline handler powerpc: kprobes: Use generic kretprobe trampoline handler parisc: kprobes: Use generic kretprobe trampoline handler mips: kprobes: Use generic kretprobe trampoline handler ia64: kprobes: Use generic kretprobe trampoline handler csky: kprobes: Use generic kretprobe trampoline handler arc: kprobes: Use generic kretprobe trampoline handler arm64: kprobes: Use generic kretprobe trampoline handler arm: kprobes: Use generic kretprobe trampoline handler x86/kprobes: Use generic kretprobe trampoline handler kprobes: Add generic kretprobe trampoline handler
2020-10-12Merge tag 'core-build-2020-10-12' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull orphan section checking from Ingo Molnar: "Orphan link sections were a long-standing source of obscure bugs, because the heuristics that various linkers & compilers use to handle them (include these bits into the output image vs discarding them silently) are both highly idiosyncratic and also version dependent. Instead of this historically problematic mess, this tree by Kees Cook (et al) adds build time asserts and build time warnings if there's any orphan section in the kernel or if a section is not sized as expected. And because we relied on so many silent assumptions in this area, fix a metric ton of dependencies and some outright bugs related to this, before we can finally enable the checks on the x86, ARM and ARM64 platforms" * tag 'core-build-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) x86/boot/compressed: Warn on orphan section placement x86/build: Warn on orphan section placement arm/boot: Warn on orphan section placement arm/build: Warn on orphan section placement arm64/build: Warn on orphan section placement x86/boot/compressed: Add missing debugging sections to output x86/boot/compressed: Remove, discard, or assert for unwanted sections x86/boot/compressed: Reorganize zero-size section asserts x86/build: Add asserts for unwanted sections x86/build: Enforce an empty .got.plt section x86/asm: Avoid generating unused kprobe sections arm/boot: Handle all sections explicitly arm/build: Assert for unwanted sections arm/build: Add missing sections arm/build: Explicitly keep .ARM.attributes sections arm/build: Refactor linker script headers arm64/build: Assert for unwanted sections arm64/build: Add missing DWARF sections arm64/build: Use common DISCARDS in linker script arm64/build: Remove .eh_frame* sections due to unwind tables ...
2020-10-12MIPS: cpu-probe: remove MIPS_CPU_BP_GHIST option bitThomas Bogendoerfer1-6/+4
MIPS_CPU_BP_GHIST is only set two times and more or less immediately used in cpu-probe.c itself. Remove this option to make room in options word. Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-10-12MIPS: cpu-probe: introduce exclusive R3k CPU probeThomas Bogendoerfer2-1/+178
Running a kernel on a R3k of machine definitly will never see one of the newer CPU cores. And since R3k system usually are low on memory we could save quite some kbytes: text data bss dec hex filename 15070 88 32 15190 3b56 arch/mips/kernel/cpu-probe.o 844 4 16 864 360 arch/mips/kernel/cpu-r3k-probe.o Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-10-12MIPS: cpu-probe: move fpu probing/handling into its own fileThomas Bogendoerfer4-324/+364
cpu-probe.c has grown when supporting more and more CPUs and there are use cases where probing for all the CPUs isn't useful like running on a R3k system. But still the fpu handling is nearly the same. For sharing put the fpu code into it's own file. Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-10-12MIPS: replace add_memory_region with memblockThomas Bogendoerfer2-69/+6
add_memory_region was the old interface for registering memory and was already changed to used memblock internaly. Replace it by directly calling memblock functions. Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-10-06dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>Christoph Hellwig1-1/+1
Merge dma-contiguous.h into dma-map-ops.h, after removing the comment describing the contiguous allocator into kernel/dma/contigous.c. Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-03mm: remove compat_process_vm_{readv,writev}Christoph Hellwig2-4/+4
Now that import_iovec handles compat iovecs, the native syscalls can be used for the compat case as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03fs: remove compat_sys_vmspliceChristoph Hellwig2-2/+2
Now that import_iovec handles compat iovecs, the native vmsplice syscall can be used for the compat case as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>