kernel.git/arch/riscv/include/asm/pgtable.h, branch linux-5.13.y

riscv: Ensure BPF_JIT_REGION_START aligned with PMD size

2021-06-19T04:10:05Z

Andreas reported commit fc8504765ec5 ("riscv: bpf: Avoid breaking W^X") breaks booting with one kind of defconfig, I reproduced a kernel panic with the defconfig: [ 0.138553] Unable to handle kernel paging request at virtual address ffffffff81201220 [ 0.139159] Oops [#1] [ 0.139303] Modules linked in: [ 0.139601] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc5-default+ #1 [ 0.139934] Hardware name: riscv-virtio,qemu (DT) [ 0.140193] epc : __memset+0xc4/0xfc [ 0.140416] ra : skb_flow_dissector_init+0x1e/0x82 [ 0.140609] epc : ffffffff8029806c ra : ffffffff8033be78 sp : ffffffe001647da0 [ 0.140878] gp : ffffffff81134b08 tp : ffffffe001654380 t0 : ffffffff81201158 [ 0.141156] t1 : 0000000000000002 t2 : 0000000000000154 s0 : ffffffe001647dd0 [ 0.141424] s1 : ffffffff80a43250 a0 : ffffffff81201220 a1 : 0000000000000000 [ 0.141654] a2 : 000000000000003c a3 : ffffffff81201258 a4 : 0000000000000064 [ 0.141893] a5 : ffffffff8029806c a6 : 0000000000000040 a7 : ffffffffffffffff [ 0.142126] s2 : ffffffff81201220 s3 : 0000000000000009 s4 : ffffffff81135088 [ 0.142353] s5 : ffffffff81135038 s6 : ffffffff8080ce80 s7 : ffffffff80800438 [ 0.142584] s8 : ffffffff80bc6578 s9 : 0000000000000008 s10: ffffffff806000ac [ 0.142810] s11: 0000000000000000 t3 : fffffffffffffffc t4 : 0000000000000000 [ 0.143042] t5 : 0000000000000155 t6 : 00000000000003ff [ 0.143220] status: 0000000000000120 badaddr: ffffffff81201220 cause: 000000000000000f [ 0.143560] [] __memset+0xc4/0xfc [ 0.143859] [] init_default_flow_dissectors+0x22/0x60 [ 0.144092] [] do_one_initcall+0x3e/0x168 [ 0.144278] [] kernel_init_freeable+0x1c8/0x224 [ 0.144479] [] kernel_init+0x12/0x110 [ 0.144658] [] ret_from_exception+0x0/0xc [ 0.145124] ---[ end trace f1e9643daa46d591 ]--- After some investigation, I think I found the root cause: commit 2bfc6cd81bd ("move kernel mapping outside of linear mapping") moves BPF JIT region after the kernel: | #define BPF_JIT_REGION_START PFN_ALIGN((unsigned long)&_end) The &_end is unlikely aligned with PMD size, so the front bpf jit region sits with part of kernel .data section in one PMD size mapping. But kernel is mapped in PMD SIZE, when bpf_jit_binary_lock_ro() is called to make the first bpf jit prog ROX, we will make part of kernel .data section RO too, so when we write to, for example memset the .data section, MMU will trigger a store page fault. To fix the issue, we need to ensure the BPF JIT region is PMD size aligned. This patch acchieve this goal by restoring the BPF JIT region to original position, I.E the 128MB before kernel .text section. The modification to kasan_init.c is inspired by Alexandre. Fixes: fc8504765ec5 ("riscv: bpf: Avoid breaking W^X") Reported-by: Andreas Schwab Signed-off-by: Jisheng Zhang Signed-off-by: Palmer Dabbelt

RISC-V: Always define XIP_FIXUP

2021-05-01T15:53:41Z

XIP depends on MMU, but XIP_FIXUP is used throughout the kernel in order to avoid excessive ifdefs. This just makes sure to always define XIP_FIXUP, which will fix MMU=n builds. XIP_OFFSET is used by assembly but XIP_FIXUP is C-only, so they're split. Fixes: 44c922572952 ("RISC-V: enable XIP") Reported-by: Guenter Roeck Signed-off-by: Palmer Dabbelt Tested-by: Alexandre Ghiti Signed-off-by: Palmer Dabbelt

RISC-V: enable XIP

2021-04-26T15:31:28Z

Introduce XIP (eXecute In Place) support for RISC-V platforms. It allows code to be executed directly from non-volatile storage directly addressable by the CPU, such as QSPI NOR flash which can be found on many RISC-V platforms. This makes way for significant optimization of RAM footprint. The XIP kernel is not compressed since it has to run directly from flash, so it will occupy more space on the non-volatile storage. The physical flash address used to link the kernel object files and for storing it has to be known at compile time and is represented by a Kconfig option. XIP on RISC-V will for the time being only work on MMU-enabled kernels. Signed-off-by: Vitaly Wool [Alex: Rebase on top of "Move kernel mapping outside the linear mapping" ] Signed-off-by: Alexandre Ghiti [Palmer: disable XIP for allyesconfig] Signed-off-by: Palmer Dabbelt

riscv: Move kernel mapping outside of linear mapping

2021-04-26T15:25:04Z

This is a preparatory patch for relocatable kernel and sv48 support. The kernel used to be linked at PAGE_OFFSET address therefore we could use the linear mapping for the kernel mapping. But the relocated kernel base address will be different from PAGE_OFFSET and since in the linear mapping, two different virtual addresses cannot point to the same physical address, the kernel mapping needs to lie outside the linear mapping so that we don't have to copy it at the same physical offset. The kernel mapping is moved to the last 2GB of the address space, BPF is now always after the kernel and modules use the 2GB memory range right before the kernel, so BPF and modules regions do not overlap. KASLR implementation will simply have to move the kernel in the last 2GB range and just take care of leaving enough space for BPF. In addition, by moving the kernel to the end of the address space, both sv39 and sv48 kernels will be exactly the same without needing to be relocated at runtime. Suggested-by: Arnd Bergmann Signed-off-by: Alexandre Ghiti [Palmer: Squash the STRICT_RWX fix, and a !MMU fix] Signed-off-by: Palmer Dabbelt

Merge tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

2021-02-26T18:28:35Z

Pull RISC-V updates from Palmer Dabbelt: "A handful of new RISC-V related patches for this merge window: - A check to ensure drivers are properly using uaccess. This isn't manifesting with any of the drivers I'm currently using, but may catch errors in new drivers. - Some preliminary support for the FU740, along with the HiFive Unleashed it will appear on. - NUMA support for RISC-V, which involves making the arm64 code generic. - Support for kasan on the vmalloc region. - A handful of new drivers for the Kendryte K210, along with the DT plumbing required to boot on a handful of K210-based boards. - Support for allocating ASIDs. - Preliminary support for kernels larger than 128MiB. - Various other improvements to our KASAN support, including the utilization of huge pages when allocating the KASAN regions. We may have already found a bug with the KASAN_VMALLOC code, but it's passing my tests. There's a fix in the works, but that will probably miss the merge window. * tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (75 commits) riscv: Improve kasan population by using hugepages when possible riscv: Improve kasan population function riscv: Use KASAN_SHADOW_INIT define for kasan memory initialization riscv: Improve kasan definitions riscv: Get rid of MAX_EARLY_MAPPING_SIZE soc: canaan: Sort the Makefile alphabetically riscv: Disable KSAN_SANITIZE for vDSO riscv: Remove unnecessary declaration riscv: Add Canaan Kendryte K210 SD card defconfig riscv: Update Canaan Kendryte K210 defconfig riscv: Add Kendryte KD233 board device tree riscv: Add SiPeed MAIXDUINO board device tree riscv: Add SiPeed MAIX GO board device tree riscv: Add SiPeed MAIX DOCK board device tree riscv: Add SiPeed MAIX BiT board device tree riscv: Update Canaan Kendryte K210 device tree dt-bindings: add resets property to dw-apb-timer dt-bindings: fix sifive gpio properties dt-bindings: update sifive uart compatible string dt-bindings: update sifive clint compatible string ...

riscv: Add support pte_protnone and pmd_protnone if CONFIG_NUMA_BALANCING

2021-01-14T23:08:57Z

These two functions are used to distinguish between PROT_NONENUMA protections and hinting fault protections. Signed-off-by: Greentime Hu Reviewed-by: Anup Patel Reviewed-by: Palmer Dabbelt Signed-off-by: Palmer Dabbelt

riscv: Separate memory init from paging init

2021-01-14T23:08:56Z

Currently, we perform some memory init functions in paging init. But, that will be an issue for NUMA support where DT needs to be flattened before numa initialization and memblock_present can only be called after numa initialization. Move memory initialization related functions to a separate function. Signed-off-by: Atish Patra Reviewed-by: Greentime Hu Reviewed-by: Anup Patel Reviewed-by: Palmer Dabbelt Signed-off-by: Palmer Dabbelt

riscv: Drop a duplicated PAGE_KERNEL_EXEC

2021-01-09T22:18:31Z

commit b91540d52a08 ("RISC-V: Add EFI runtime services") add a duplicated PAGE_KERNEL_EXEC, kill it. Signed-off-by: Kefeng Wang Reviewed-by: Pekka Enberg Reviewed-by: Atish Patra Fixes: b91540d52a08 ("RISC-V: Add EFI runtime services") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt

arch, mm: restore dependency of __kernel_map_pages() on DEBUG_PAGEALLOC

2020-12-15T20:13:43Z

The design of DEBUG_PAGEALLOC presumes that __kernel_map_pages() must never fail. With this assumption is wouldn't be safe to allow general usage of this function. Moreover, some architectures that implement __kernel_map_pages() have this function guarded by #ifdef DEBUG_PAGEALLOC and some refuse to map/unmap pages when page allocation debugging is disabled at runtime. As all the users of __kernel_map_pages() were converted to use debug_pagealloc_map_pages() it is safe to make it available only when DEBUG_PAGEALLOC is set. Link: https://lkml.kernel.org/r/20201109192128.960-4-rppt@kernel.org Signed-off-by: Mike Rapoport Acked-by: David Hildenbrand Acked-by: Kirill A. Shutemov Cc: Albert Ou Cc: Andy Lutomirski Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Christoph Lameter Cc: Dave Hansen Cc: David Rientjes Cc: "David S. Miller" Cc: "Edgecombe, Rick P" Cc: Heiko Carstens Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Joonsoo Kim Cc: Len Brown Cc: Michael Ellerman Cc: Palmer Dabbelt Cc: Paul Mackerras Cc: Paul Walmsley Cc: Pavel Machek Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: "Rafael J. Wysocki" Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

RISC-V: Add EFI runtime services

2020-10-02T21:31:28Z

This patch adds EFI runtime service support for RISC-V. Signed-off-by: Atish Patra [ardb: - Remove the page check] Signed-off-by: Ard Biesheuvel Acked-by: Ard Biesheuvel Signed-off-by: Palmer Dabbelt