| Message ID | 20230324155421.271544-1-alexghiti@rivosinc.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | riscv: Use PUD/P4D/PGD pages for the linear mapping | expand |
On Fri, Mar 24, 2023 at 9:24 PM Alexandre Ghiti <alexghiti@rivosinc.com> wrote: > > This patchset intends to improve tlb utilization by using hugepages for > the linear mapping. > > As reported by Anup in v6, when STRICT_KERNEL_RWX is enabled, we must > take care of isolating the kernel text and rodata so that they are not > mapped with a PUD mapping which would then assign wrong permissions to > the whole region: it is achieved the same way as arm64 by using the > memblock nomap API which isolates those regions and re-merge them afterwards > thus avoiding any issue with the system resources tree creation. > > base-commit-tag: v6.3-rc1 > > v9: > - Remove new API and arm64 patches as it created more issues than it > solved, thanks Anup for reporting those bugs! > - Add a patch that moves the linear mapping creation outside of setup_vm_final > - Use nomap API like arm64 > - Removed RB from Andrew and Anup as the patch changed its logic > - Fix kernel rodata size computation > > v8: > - Fix rv32, as reported by Anup > - Do not modify memblock_isolate_range and fixes comment, as suggested by Mike > - Use the new memblock API for crash kernel too in arm64, as suggested by Andrew > - Fix arm64 double mapping (which to me did not work in v7), but ends up not > being pretty at all, will wait for comments from arm64 reviewers, but > this patch can easily be dropped if they do not want it. > > v7: > - Fix Anup bug report by introducing memblock_isolate_memory which > allows us to split the memblock mappings and then avoid to map the > the PUD which contains the kernel as read only > - Add a patch to arm64 to use this newly introduced API > > v6: > - quiet LLVM warning by casting phys_ram_base into an unsigned long > > v5: > - Fix nommu builds by getting rid of riscv_pfn_base in patch 1, thanks > Conor > - Add RB from Andrew > > v4: > - Rebase on top of v6.2-rc3, as noted by Conor > - Add Acked-by Rob > > v3: > - Change the comment about initrd_start VA conversion so that it fits > ARM64 and RISCV64 (and others in the future if needed), as suggested > by Rob > > v2: > - Add a comment on why RISCV64 does not need to set initrd_start/end that > early in the boot process, as asked by Rob > > Alexandre Ghiti (3): > riscv: Get rid of riscv_pfn_base variable > riscv: Move the linear mapping creation in its own function > riscv: Use PUD/P4D/PGD pages for the linear mapping I have tested this series again on QEMU RV64 and RV32. I also tried KVM RV64 and RV32, this works fine as well. > > arch/riscv/include/asm/page.h | 19 ++++++- > arch/riscv/mm/init.c | 102 ++++++++++++++++++++++++++-------- > arch/riscv/mm/physaddr.c | 16 ++++++ > drivers/of/fdt.c | 11 ++-- > 4 files changed, 118 insertions(+), 30 deletions(-) > > -- > 2.37.2 > Regards, Anup
On Fri, 24 Mar 2023 16:54:18 +0100, Alexandre Ghiti wrote: > This patchset intends to improve tlb utilization by using hugepages for > the linear mapping. > > As reported by Anup in v6, when STRICT_KERNEL_RWX is enabled, we must > take care of isolating the kernel text and rodata so that they are not > mapped with a PUD mapping which would then assign wrong permissions to > the whole region: it is achieved the same way as arm64 by using the > memblock nomap API which isolates those regions and re-merge them afterwards > thus avoiding any issue with the system resources tree creation. > > [...] Applied, thanks! [1/3] riscv: Get rid of riscv_pfn_base variable https://git.kernel.org/palmer/c/a7407a1318a9 [2/3] riscv: Move the linear mapping creation in its own function https://git.kernel.org/palmer/c/8589e346bbb6 [3/3] riscv: Use PUD/P4D/PGD pages for the linear mapping https://git.kernel.org/palmer/c/3335068f8721 Best regards,
Hello: This series was applied to riscv/linux.git (for-next) by Palmer Dabbelt <palmer@rivosinc.com>: On Fri, 24 Mar 2023 16:54:18 +0100 you wrote: > This patchset intends to improve tlb utilization by using hugepages for > the linear mapping. > > As reported by Anup in v6, when STRICT_KERNEL_RWX is enabled, we must > take care of isolating the kernel text and rodata so that they are not > mapped with a PUD mapping which would then assign wrong permissions to > the whole region: it is achieved the same way as arm64 by using the > memblock nomap API which isolates those regions and re-merge them afterwards > thus avoiding any issue with the system resources tree creation. > > [...] Here is the summary with links: - [v9,1/3] riscv: Get rid of riscv_pfn_base variable https://git.kernel.org/riscv/c/a7407a1318a9 - [v9,2/3] riscv: Move the linear mapping creation in its own function https://git.kernel.org/riscv/c/8589e346bbb6 - [v9,3/3] riscv: Use PUD/P4D/PGD pages for the linear mapping https://git.kernel.org/riscv/c/3335068f8721 You are awesome, thank you!