Hi Nylon, On Thu, Jan 18, 2024 at 9:23 AM Nylon Chen <nylon.chen@xxxxxxxxxx> wrote: > > > On 3/23/23 15:55, Anup Patel wrote: > > > On Thu, Mar 23, 2023 at 6:24 PM Alexandre Ghiti <alexghiti@xxxxxxxxxxxx> wrote: > > >> Hi Anup, > > >> > > >> On Thu, Mar 23, 2023 at 1:18 PM Anup Patel <apatel@xxxxxxxxxxxxxxxx> wrote: > > >>> Hi Alex, > > >>> > > >>> On Thu, Mar 16, 2023 at 6:48 PM Alexandre Ghiti <alexghiti@xxxxxxxxxxxx> 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 by introducing a new memblock API. > > >>>> > > >>>> Another patch makes use of this new API in arm64 which used some sort of > > >>>> hack to solve this issue: it was built/boot tested successfully. > > >>>> > > >>>> base-commit-tag: v6.3-rc1 > > >>>> > > >>>> 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 (4): > > >>>> riscv: Get rid of riscv_pfn_base variable > > >>>> mm: Introduce memblock_isolate_memory > > >>>> arm64: Make use of memblock_isolate_memory for the linear mapping > > >>>> riscv: Use PUD/P4D/PGD pages for the linear mapping > > >>> Kernel boot fine on RV64 but there is a failure which is still not > > >>> addressed. You can see this failure as following message in > > >>> kernel boot log: > > >>> 0.000000] Failed to add a System RAM resource at 80200000 > > >> Hmmm I don't get that in any of my test configs, would you mind > > >> sharing yours and your qemu command line? > > > Try alexghiti_test branch at > > > https://github.com/avpatel/linux.git > > > > > > I am building the kernel using defconfig and my rootfs is > > > based on busybox. > > > > > > My QEMU command is: > > > qemu-system-riscv64 -M virt -m 512M -nographic -bios > > > opensbi/build/platform/generic/firmware/fw_dynamic.bin -kernel > > > ./build-riscv64/arch/riscv/boot/Image -append "root=/dev/ram rw > > > console=ttyS0 earlycon" -initrd ./rootfs_riscv64.img -smp 4 > > > > > > So splitting memblock.memory is the culprit, it "confuses" the resources > > addition and I can only find hacky ways to fix that... > Hi Alexandre, > > We encountered the same error as Anup. After adding your patch > (3335068f87217ea59d08f462187dc856652eea15), we will not encounter the > error again. > > What I have observed so far is > > - before your patch > When merging consecutive memblocks, if the memblock types are different, > they will be merged into reserved > - after your patch > When consecutive memblocks are merged, if the memblock types are > different, they will be merged into memory. > > Such a result will cause the memory location of OpenSBI to be changed > from reserved to memory. Will this have any side effects? I guess it will end up in the memory pool and pages from openSBI region will be allocated, so we should see very quickly bad stuff happening (either PMP violation or M-mode ecall never returning/trapping/etc). But I don't observe the same thing, I always see the openSBI region being reserved: reserved[0x0] [0x0000000080000000-0x000000008007ffff], 0x0000000000080000 bytes flags: 0x0 Can you elaborate a bit more about "When consecutive memblocks are merged, if the memblock types are different, they will be merged into memory"? Where/when does this merge happen? Can you give me a config file and a kernel revision so that I can take a look? Thanks, Alex > > > > So given that the arm64 patch with the new API is not pretty and that > > the simplest solution is to re-merge the memblock regions afterwards > > (which is done by memblock_clear_nomap), I'll drop the new API and the > > arm64 patch to use the nomap API like arm64: I'll take advantage of that > > to clean setup_vm_final which I have wanted to do for a long time. > > > > @Mike Thanks for you reviews! > > > > @Anup Thanks for all your bug reports on this patchset, I have to > > improve my test flow (it is in the work :)). > > > > > > > Regards, > > > Anup > > > > > >> Thanks > > >> > > >>> Regards, > > >>> Anup > > >>> > > >>>> arch/arm64/mm/mmu.c | 25 +++++++++++------ > > >>>> arch/riscv/include/asm/page.h | 19 +++++++++++-- > > >>>> arch/riscv/mm/init.c | 53 ++++++++++++++++++++++++++++------- > > >>>> arch/riscv/mm/physaddr.c | 16 +++++++++++ > > >>>> drivers/of/fdt.c | 11 ++++---- > > >>>> include/linux/memblock.h | 1 + > > >>>> mm/memblock.c | 20 +++++++++++++ > > >>>> 7 files changed, 119 insertions(+), 26 deletions(-) > > >>>> > > >>>> -- > > >>>> 2.37.2 > > >>>> > > > _______________________________________________ > > > linux-riscv mailing list > > > linux-riscv@xxxxxxxxxxxxxxxxxxx > > > http://lists.infradead.org/mailman/listinfo/linux-riscv > > > > _______________________________________________ > > linux-riscv mailing list > > linux-riscv@xxxxxxxxxxxxxxxxxxx > > http://lists.infradead.org/mailman/listinfo/linux-riscv
