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2020-06-09mmap locking API: convert mmap_sem commentsMichel Lespinasse
Convert comments that reference mmap_sem to reference mmap_lock instead. [akpm@linux-foundation.org: fix up linux-next leftovers] [akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil] [akpm@linux-foundation.org: more linux-next fixups, per Michel] Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mmap locking API: convert mmap_sem API commentsMichel Lespinasse
Convert comments that reference old mmap_sem APIs to reference corresponding new mmap locking APIs instead. Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-12-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse
This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02mm: allow VM_FAULT_RETRY for multiple timesPeter Xu
The idea comes from a discussion between Linus and Andrea [1]. Before this patch we only allow a page fault to retry once. We achieved this by clearing the FAULT_FLAG_ALLOW_RETRY flag when doing handle_mm_fault() the second time. This was majorly used to avoid unexpected starvation of the system by looping over forever to handle the page fault on a single page. However that should hardly happen, and after all for each code path to return a VM_FAULT_RETRY we'll first wait for a condition (during which time we should possibly yield the cpu) to happen before VM_FAULT_RETRY is really returned. This patch removes the restriction by keeping the FAULT_FLAG_ALLOW_RETRY flag when we receive VM_FAULT_RETRY. It means that the page fault handler now can retry the page fault for multiple times if necessary without the need to generate another page fault event. Meanwhile we still keep the FAULT_FLAG_TRIED flag so page fault handler can still identify whether a page fault is the first attempt or not. Then we'll have these combinations of fault flags (only considering ALLOW_RETRY flag and TRIED flag): - ALLOW_RETRY and !TRIED: this means the page fault allows to retry, and this is the first try - ALLOW_RETRY and TRIED: this means the page fault allows to retry, and this is not the first try - !ALLOW_RETRY and !TRIED: this means the page fault does not allow to retry at all - !ALLOW_RETRY and TRIED: this is forbidden and should never be used In existing code we have multiple places that has taken special care of the first condition above by checking against (fault_flags & FAULT_FLAG_ALLOW_RETRY). This patch introduces a simple helper to detect the first retry of a page fault by checking against both (fault_flags & FAULT_FLAG_ALLOW_RETRY) and !(fault_flag & FAULT_FLAG_TRIED) because now even the 2nd try will have the ALLOW_RETRY set, then use that helper in all existing special paths. One example is in __lock_page_or_retry(), now we'll drop the mmap_sem only in the first attempt of page fault and we'll keep it in follow up retries, so old locking behavior will be retained. This will be a nice enhancement for current code [2] at the same time a supporting material for the future userfaultfd-writeprotect work, since in that work there will always be an explicit userfault writeprotect retry for protected pages, and if that cannot resolve the page fault (e.g., when userfaultfd-writeprotect is used in conjunction with swapped pages) then we'll possibly need a 3rd retry of the page fault. It might also benefit other potential users who will have similar requirement like userfault write-protection. GUP code is not touched yet and will be covered in follow up patch. Please read the thread below for more information. [1] https://lore.kernel.org/lkml/20171102193644.GB22686@redhat.com/ [2] https://lore.kernel.org/lkml/20181230154648.GB9832@redhat.com/ Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Suggested-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Brian Geffon <bgeffon@google.com> Cc: Bobby Powers <bobbypowers@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: Denis Plotnikov <dplotnikov@virtuozzo.com> Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Kirill A . Shutemov" <kirill@shutemov.name> Cc: Martin Cracauer <cracauer@cons.org> Cc: Marty McFadden <mcfadden8@llnl.gov> Cc: Matthew Wilcox <willy@infradead.org> Cc: Maya Gokhale <gokhale2@llnl.gov> Cc: Mel Gorman <mgorman@suse.de> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Pavel Emelyanov <xemul@openvz.org> Link: http://lkml.kernel.org/r/20200220160246.9790-1-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02mm: introduce FAULT_FLAG_DEFAULTPeter Xu
Although there're tons of arch-specific page fault handlers, most of them are still sharing the same initial value of the page fault flags. Say, merely all of the page fault handlers would allow the fault to be retried, and they also allow the fault to respond to SIGKILL. Let's define a default value for the fault flags to replace those initial page fault flags that were copied over. With this, it'll be far easier to introduce new fault flag that can be used by all the architectures instead of touching all the archs. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Brian Geffon <bgeffon@google.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Bobby Powers <bobbypowers@gmail.com> Cc: Denis Plotnikov <dplotnikov@virtuozzo.com> Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Kirill A . Shutemov" <kirill@shutemov.name> Cc: Martin Cracauer <cracauer@cons.org> Cc: Marty McFadden <mcfadden8@llnl.gov> Cc: Matthew Wilcox <willy@infradead.org> Cc: Maya Gokhale <gokhale2@llnl.gov> Cc: Mel Gorman <mgorman@suse.de> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Pavel Emelyanov <xemul@openvz.org> Link: http://lkml.kernel.org/r/20200220160238.9694-1-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02mm: introduce fault_signal_pending()Peter Xu
For most architectures, we've got a quick path to detect fatal signal after a handle_mm_fault(). Introduce a helper for that quick path. It cleans the current codes a bit so we don't need to duplicate the same check across archs. More importantly, this will be an unified place that we handle the signal immediately right after an interrupted page fault, so it'll be much easier for us if we want to change the behavior of handling signals later on for all the archs. Note that currently only part of the archs are using this new helper, because some archs have their own way to handle signals. In the follow up patches, we'll try to apply this helper to all the rest of archs. Another note is that the "regs" parameter in the new helper is not used yet. It'll be used very soon. Now we kept it in this patch only to avoid touching all the archs again in the follow up patches. [peterx@redhat.com: fix sparse warnings] Link: http://lkml.kernel.org/r/20200311145921.GD479302@xz-x1 Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Brian Geffon <bgeffon@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Bobby Powers <bobbypowers@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: Denis Plotnikov <dplotnikov@virtuozzo.com> Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Kirill A . Shutemov" <kirill@shutemov.name> Cc: Martin Cracauer <cracauer@cons.org> Cc: Marty McFadden <mcfadden8@llnl.gov> Cc: Matthew Wilcox <willy@infradead.org> Cc: Maya Gokhale <gokhale2@llnl.gov> Cc: Mel Gorman <mgorman@suse.de> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Pavel Emelyanov <xemul@openvz.org> Link: http://lkml.kernel.org/r/20200220155353.8676-4-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-05riscv: abstract out CSR names for supervisor vs machine modeChristoph Hellwig
Many of the privileged CSRs exist in a supervisor and machine version that are used very similarly. Provide versions of the CSR names and fields that map to either the S-mode or M-mode variant depending on a new CONFIG_RISCV_M_MODE kconfig symbol. Contains contributions from Damien Le Moal <Damien.LeMoal@wdc.com> and Paul Walmsley <paul.walmsley@sifive.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> # for drivers/clocksource, drivers/irqchip [paul.walmsley@sifive.com: updated to apply] Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-28riscv: add prototypes for assembly language functions from head.SPaul Walmsley
Add prototypes for assembly language functions defined in head.S, and include these prototypes into C source files that call those functions. This patch resolves the following warnings from sparse: arch/riscv/kernel/setup.c:39:10: warning: symbol 'hart_lottery' was not declared. Should it be static? arch/riscv/kernel/setup.c:42:13: warning: symbol 'parse_dtb' was not declared. Should it be static? arch/riscv/kernel/smpboot.c:33:6: warning: symbol '__cpu_up_stack_pointer' was not declared. Should it be static? arch/riscv/kernel/smpboot.c:34:6: warning: symbol '__cpu_up_task_pointer' was not declared. Should it be static? arch/riscv/mm/fault.c:25:17: warning: symbol 'do_page_fault' was not declared. Should it be static? This change should have no functional impact. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-07-08Merge branch 'siginfo-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull force_sig() argument change from Eric Biederman: "A source of error over the years has been that force_sig has taken a task parameter when it is only safe to use force_sig with the current task. The force_sig function is built for delivering synchronous signals such as SIGSEGV where the userspace application caused a synchronous fault (such as a page fault) and the kernel responded with a signal. Because the name force_sig does not make this clear, and because the force_sig takes a task parameter the function force_sig has been abused for sending other kinds of signals over the years. Slowly those have been fixed when the oopses have been tracked down. This set of changes fixes the remaining abusers of force_sig and carefully rips out the task parameter from force_sig and friends making this kind of error almost impossible in the future" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits) signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus signal: Remove the signal number and task parameters from force_sig_info signal: Factor force_sig_info_to_task out of force_sig_info signal: Generate the siginfo in force_sig signal: Move the computation of force into send_signal and correct it. signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal signal: Remove the task parameter from force_sig_fault signal: Use force_sig_fault_to_task for the two calls that don't deliver to current signal: Explicitly call force_sig_fault on current signal/unicore32: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from ptrace_break signal/nds32: Remove tsk parameter from send_sigtrap signal/riscv: Remove tsk parameter from do_trap signal/sh: Remove tsk parameter from force_sig_info_fault signal/um: Remove task parameter from send_sigtrap signal/x86: Remove task parameter from send_sigtrap signal: Remove task parameter from force_sig_mceerr signal: Remove task parameter from force_sig signal: Remove task parameter from force_sigsegv ...
2019-06-26riscv: mm: Fix code commentShihPo Hung
Fix the comment since vmalloc_fault doesn't reach flush_tlb_fix_spurious_fault. Signed-off-by: ShihPo Hung <shihpo.hung@sifive.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: linux-riscv@lists.infradead.org Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-06-17Merge tag 'riscv-for-v5.2/fixes-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Paul Walmsley: "This contains fixes, defconfig, and DT data changes for the v5.2-rc series. The fixes are relatively straightforward: - Addition of a TLB fence in the vmalloc_fault path, so the CPU doesn't enter an infinite page fault loop - Readdition of the pm_power_off export, so device drivers that reassign it can now be built as modules - A udelay() fix for RV32, fixing a miscomputation of the delay time - Removal of deprecated smp_mb__*() barriers This also adds initial DT data infrastructure for arch/riscv, along with initial data for the SiFive FU540-C000 SoC and the corresponding HiFive Unleashed board. We also update the RV64 defconfig to include some core drivers for the FU540 in the build" * tag 'riscv-for-v5.2/fixes-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: remove unused barrier defines riscv: mm: synchronize MMU after pte change riscv: dts: add initial board data for the SiFive HiFive Unleashed riscv: dts: add initial support for the SiFive FU540-C000 SoC dt-bindings: riscv: convert cpu binding to json-schema dt-bindings: riscv: sifive: add YAML documentation for the SiFive FU540 arch: riscv: add support for building DTB files from DT source data riscv: Fix udelay in RV32. riscv: export pm_power_off again RISC-V: defconfig: enable clocks, serial console
2019-06-17riscv: mm: synchronize MMU after pte changeShihPo Hung
Because RISC-V compliant implementations can cache invalid entries in TLB, an SFENCE.VMA is necessary after changes to the page table. This patch adds an SFENCE.vma for the vmalloc_fault path. Signed-off-by: ShihPo Hung <shihpo.hung@sifive.com> [paul.walmsley@sifive.com: reversed tab->whitespace conversion, wrapped comment lines] Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: linux-riscv@lists.infradead.org Cc: stable@vger.kernel.org
2019-05-29signal/riscv: Remove tsk parameter from do_trapEric W. Biederman
The do_trap function is always called with tsk == current. Make that obvious by removing the tsk parameter. This also makes it clear that do_trap calls force_sig_fault on the current task. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 120Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see the file copying or write to the free software foundation inc extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 12 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190523091651.231300438@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-16riscv: fix locking violation in page fault handlerAndreas Schwab
When a user mode process accesses an address in the vmalloc area do_page_fault tries to unlock the mmap semaphore when it isn't locked. Signed-off-by: Andreas Schwab <schwab@suse.de> [Palmer: Duplicated code instead of a goto] Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-05-16RISC-V: Access CSRs using CSR numbersAnup Patel
We should prefer accessing CSRs using their CSR numbers because: 1. It compiles fine with older toolchains. 2. We can use latest CSR names in #define macro names of CSR numbers as-per RISC-V spec. 3. We can access newly added CSRs even if toolchain does not recognize newly addes CSRs by name. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-17mm: convert return type of handle_mm_fault() caller to vm_fault_tSouptick Joarder
Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t") In this patch all the caller of handle_mm_fault() are changed to return vm_fault_t type. Link: http://lkml.kernel.org/r/20180617084810.GA6730@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Tony Luck <tony.luck@intel.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Michal Simek <monstr@monstr.eu> Cc: James Hogan <jhogan@kernel.org> Cc: Ley Foon Tan <lftan@altera.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: David S. Miller <davem@davemloft.net> Cc: Richard Weinberger <richard@nod.at> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-07Merge tag 'riscv-for-linus-4.16-merge_window' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux Pull RISC-V updates from Palmer Dabbelt: "This contains the fixes we'd like to target for the 4.16 merge window. It's not as much as I was originally hoping to do but between glibc, the chip, and FOSDEM there just wasn't enough time to get everything put together. As such, this merge window is essentially just going to be small changes. This includes mostly cleanups: - A build fix failure to the audit test cases. RISC-V doesn't have renameat because the generic syscall ABI moved to renameat2 by the time of our port. The syscall audit test cases don't understand this, so I added a trivial fix. This went through mailing list review during the 4.15 merge window, but nobody has picked it up so I think it's best to just do this here. - The removal of our command-line argument processing code. The "mem_end" stuff was broken and the rest duplicated generic device tree code. The generic code was already being called. - Some unused/redundant code has been removed, including __ARCH_HAVE_MMU, current_pgdir, and the initialization of init_mm.pgd. - SUM is disabled upon taking a trap, which means that user memory is protected during traps taking inside copy_{to,from}_user(). - The sptbr CSR has been renamed to satp in C code. We haven't changed the assembly code in order to maintain compatibility with binutils 2.29, which doesn't understand the new name. Additionally, we're adding some new features: - Basic ftrace support, thanks to Alan Kao! - Support for ZONE_DMA32. This is necessary for all the normal reasons, but also to deal with a deficiency in the Xilinx PCIe controller we're using on our FPGA-based systems. While the ZONE_DMA32 addition should be sufficient for most uses, it doesn't complete the fix for the Xilinx controller. - TLB shootdowns now only target the harts where they're necessary, instead of applying to all harts in the system. These patches have all been sitting on our linux-next branch for a while now. Due to time constraints this is all I feel comfortable submitting during the 4.16 merge window, hopefully we'll do better next time!" [ Note to self: "harts" is RISC-V speak for "hardware threads". I had to look that up. - Linus ] * tag 'riscv-for-linus-4.16-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: riscv: inline set_pgdir into its only caller riscv: rename sptbr to satp riscv: don't read back satp in paging_init riscv: remove the unused current_pgdir function riscv: add ZONE_DMA32 RISC-V: Limit the scope of TLB shootdowns riscv: disable SUM in the exception handler riscv: remove redundant unlikely() riscv: remove unused __ARCH_HAVE_MMU define riscv/ftrace: Add basic support RISC-V: Remove mem_end command line processing RISC-V: Remove duplicate command-line parsing logic audit: Avoid build failures on systems without renameat
2018-01-31Merge branch 'work.whack-a-mole' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull asm/uaccess.h whack-a-mole from Al Viro: "It's linux/uaccess.h, damnit... Oh, well - eventually they'll stop cropping up..." * 'work.whack-a-mole' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: asm-prototypes.h: use linux/uaccess.h, not asm/uaccess.h riscv: use linux/uaccess.h, not asm/uaccess.h... ppc: for put_user() pull linux/uaccess.h, not asm/uaccess.h
2018-01-30riscv: rename sptbr to satpChristoph Hellwig
satp is the name used by the current privileged spec 1.10, use it instead of the old name. The most recent release binutils release (2.29) doesn't know about the satp name yet, so stick to the name from the previous privileged ISA release and comment on the fact. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-07riscv: rename SR_* constants to match the specChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-12-04riscv: use linux/uaccess.h, not asm/uaccess.h...Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-26RISC-V: Paging and MMUPalmer Dabbelt
This patch contains code to manage the RISC-V MMU, including definitions of the page tables and the page walking code. Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>