Re: [PATCH v3 0/3] arm64: support page mapping percpu first chunk allocator

[Kefeng Wang]

On 2021/8/12 14:07, Kefeng Wang wrote:
> Hi Catalin and Will，
>
> The drivers/base/arch_numa.c is only shared by riscv and arm64,
>
> and the change from patch2 won't broke riscv.
>
> Could all patches be merged by arm64 tree? or any new comments?

Kindly ping...

> Many thanks.
>
> On 2021/8/9 17:37, Kefeng Wang wrote:
> > Percpu embedded first chunk allocator is the firstly option, but it
> > could fails on ARM64, eg,
> >    "percpu: max_distance=0x5fcfdc640000 too large for vmalloc space 
> > 0x781fefff0000"
> >    "percpu: max_distance=0x600000540000 too large for vmalloc space 
> > 0x7dffb7ff0000"
> >    "percpu: max_distance=0x5fff9adb0000 too large for vmalloc space 
> > 0x5dffb7ff0000"
> >
> > then we could meet "WARNING: CPU: 15 PID: 461 at vmalloc.c:3087 
> > pcpu_get_vm_areas+0x488/0x838",
> > even the system could not boot successfully.
> >
> > Let's implement page mapping percpu first chunk allocator as a fallback
> > to the embedding allocator to increase the robustness of the system.
> >
> > Also fix a crash when both NEED_PER_CPU_PAGE_FIRST_CHUNK and 
> > KASAN_VMALLOC enabled.
> >
> > Tested on ARM64 qemu with cmdline "percpu_alloc=page" based on 
> > v5.14-rc5.
> >
> > v3:
> > - search for a range that fits instead of always picking the end from
> >    vmalloc area suggested by Catalin.
> > - use NUMA_NO_NODE to avoid "virt_to_phys used for non-linear address:"
> >    issue in arm64 kasan_populate_early_vm_area_shadow().
> > - add Acked-by: Marco Elver <elver@xxxxxxxxxx> to patch v3
> >
> > V2:
> > - fix build error when CONFIG_KASAN disabled, found by lkp@xxxxxxxxx
> > - drop wrong __weak comment from kasan_populate_early_vm_area_shadow(),
> >    found by Marco Elver <elver@xxxxxxxxxx>
> >
> > Kefeng Wang (3):
> >    vmalloc: Choose a better start address in vm_area_register_early()
> >    arm64: Support page mapping percpu first chunk allocator
> >    kasan: arm64: Fix pcpu_page_first_chunk crash with KASAN_VMALLOC
> >
> >   arch/arm64/Kconfig         |  4 ++
> >   arch/arm64/mm/kasan_init.c | 16 ++++++++
> >   drivers/base/arch_numa.c   | 82 +++++++++++++++++++++++++++++++++-----
> >   include/linux/kasan.h      |  6 +++
> >   mm/kasan/init.c            |  5 +++
> >   mm/vmalloc.c               | 17 +++++---
> >   6 files changed, 115 insertions(+), 15 deletions(-)