| Message ID | 20230414081605.471375-1-vincent.chen@sifive.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | riscv: mm: execute local TLB flush after populating vmemmap | expand |
| Context | Check | Description |
|---|---|---|
| conchuod/cover_letter | success | Single patches do not need cover letters |
| conchuod/tree_selection | success | Guessed tree name to be fixes at HEAD 1b50f956c8fe |
| conchuod/fixes_present | success | Fixes tag present in non-next series |
| conchuod/maintainers_pattern | success | MAINTAINERS pattern errors before the patch: 1 and now 1 |
| conchuod/verify_signedoff | success | Signed-off-by tag matches author and committer |
| conchuod/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| conchuod/build_rv64_clang_allmodconfig | success | Errors and warnings before: 3288 this patch: 3288 |
| conchuod/module_param | success | Was 0 now: 0 |
| conchuod/build_rv64_gcc_allmodconfig | success | Errors and warnings before: 17609 this patch: 17609 |
| conchuod/build_rv32_defconfig | success | Build OK |
| conchuod/dtb_warn_rv64 | success | Errors and warnings before: 3 this patch: 3 |
| conchuod/header_inline | success | No static functions without inline keyword in header files |
| conchuod/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 28 lines checked |
| conchuod/source_inline | success | Was 0 now: 0 |
| conchuod/build_rv64_nommu_k210_defconfig | success | Build OK |
| conchuod/verify_fixes | success | Fixes tag looks correct |
| conchuod/build_rv64_nommu_virt_defconfig | success | Build OK |
On Fri, Apr 14, 2023 at 04:16:05PM +0800, Vincent Chen wrote: > The spare_init() calls memmap_populate() many times to create VA to PA > mapping for the VMEMMAP area, where all "strcut page" are located once struct > CONFIG_SPARSEMEM_VMEMMAP is defined. These "struct page" are later > initialized in the zone_sizes_init() function. However, during this > process, no sfence.vma instruction is executed for this VMEMMAP area. > This omission may cause the hart to fail to perform page table work s/work/walk/ ? > because some data related to the address translation is invisible to the > hart. To solve this issue, the local_flush_tlb_kernel_range() is called > right after the spare_init() to execute a sfence.vma instruction for the > VMEMMAP area, ensuring that all data related to the address translation > is visible to the hart. > > Fixes: d95f1a542c3d ("RISC-V: Implement sparsemem") > Signed-off-by: Vincent Chen <vincent.chen@sifive.com> > Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> > --- > arch/riscv/include/asm/tlbflush.h | 7 +++++++ > arch/riscv/mm/init.c | 5 +++++ > 2 files changed, 12 insertions(+) > > diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h > index a09196f8de68..f9d3712bd93b 100644 > --- a/arch/riscv/include/asm/tlbflush.h > +++ b/arch/riscv/include/asm/tlbflush.h > @@ -61,4 +61,11 @@ static inline void flush_tlb_kernel_range(unsigned long start, > flush_tlb_all(); > } > > +/* Flush a range of kernel pages without broadcasting */ > +static inline void local_flush_tlb_kernel_range(unsigned long start, > + unsigned long end) > +{ > + local_flush_tlb_all(); > +} > + > #endif /* _ASM_RISCV_TLBFLUSH_H */ > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index 478d6763a01a..5bd96f6c8f19 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -1231,6 +1231,10 @@ void __init misc_mem_init(void) > early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); > arch_numa_init(); > sparse_init(); > +#ifdef CONFIG_SPARSEMEM_VMEMMAP > + /* The entire VMEMMAP region has been propulated. Flush TLB for this region */ populated > + local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END); > +#endif > zone_sizes_init(); > reserve_crashkernel(); > memblock_dump_all(); > @@ -1240,6 +1244,7 @@ void __init misc_mem_init(void) > int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, > struct vmem_altmap *altmap) > { > + /* Defer the required TLB flush until the entire VMEMMAP region has been populated */ > return vmemmap_populate_basepages(start, end, node, NULL); > } > #endif > -- > 2.25.1 > Besides the typos, Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Thanks, drew
On Fri, Apr 14, 2023 at 5:14 PM Andrew Jones <ajones@ventanamicro.com> wrote: > > On Fri, Apr 14, 2023 at 04:16:05PM +0800, Vincent Chen wrote: > > The spare_init() calls memmap_populate() many times to create VA to PA > > mapping for the VMEMMAP area, where all "strcut page" are located once > > struct > > > CONFIG_SPARSEMEM_VMEMMAP is defined. These "struct page" are later > > initialized in the zone_sizes_init() function. However, during this > > process, no sfence.vma instruction is executed for this VMEMMAP area. > > This omission may cause the hart to fail to perform page table work > > s/work/walk/ ? > > > because some data related to the address translation is invisible to the > > hart. To solve this issue, the local_flush_tlb_kernel_range() is called > > right after the spare_init() to execute a sfence.vma instruction for the > > VMEMMAP area, ensuring that all data related to the address translation > > is visible to the hart. > > > > Fixes: d95f1a542c3d ("RISC-V: Implement sparsemem") > > Signed-off-by: Vincent Chen <vincent.chen@sifive.com> > > Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> > > --- > > arch/riscv/include/asm/tlbflush.h | 7 +++++++ > > arch/riscv/mm/init.c | 5 +++++ > > 2 files changed, 12 insertions(+) > > > > diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h > > index a09196f8de68..f9d3712bd93b 100644 > > --- a/arch/riscv/include/asm/tlbflush.h > > +++ b/arch/riscv/include/asm/tlbflush.h > > @@ -61,4 +61,11 @@ static inline void flush_tlb_kernel_range(unsigned long start, > > flush_tlb_all(); > > } > > > > +/* Flush a range of kernel pages without broadcasting */ > > +static inline void local_flush_tlb_kernel_range(unsigned long start, > > + unsigned long end) > > +{ > > + local_flush_tlb_all(); > > +} > > + > > #endif /* _ASM_RISCV_TLBFLUSH_H */ > > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > > index 478d6763a01a..5bd96f6c8f19 100644 > > --- a/arch/riscv/mm/init.c > > +++ b/arch/riscv/mm/init.c > > @@ -1231,6 +1231,10 @@ void __init misc_mem_init(void) > > early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); > > arch_numa_init(); > > sparse_init(); > > +#ifdef CONFIG_SPARSEMEM_VMEMMAP > > + /* The entire VMEMMAP region has been propulated. Flush TLB for this region */ > > populated > > > + local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END); > > +#endif > > zone_sizes_init(); > > reserve_crashkernel(); > > memblock_dump_all(); > > @@ -1240,6 +1244,7 @@ void __init misc_mem_init(void) > > int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, > > struct vmem_altmap *altmap) > > { > > + /* Defer the required TLB flush until the entire VMEMMAP region has been populated */ > > return vmemmap_populate_basepages(start, end, node, NULL); > > } > > #endif > > -- > > 2.25.1 > > > > Besides the typos, Thank you for finding these typos. It's really embarrassing. I will fix these issues in the patch for v3. Thanks, Vincent > > Reviewed-by: Andrew Jones <ajones@ventanamicro.com> > > Thanks, > drew
diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h index a09196f8de68..f9d3712bd93b 100644 --- a/arch/riscv/include/asm/tlbflush.h +++ b/arch/riscv/include/asm/tlbflush.h @@ -61,4 +61,11 @@ static inline void flush_tlb_kernel_range(unsigned long start, flush_tlb_all(); } +/* Flush a range of kernel pages without broadcasting */ +static inline void local_flush_tlb_kernel_range(unsigned long start, + unsigned long end) +{ + local_flush_tlb_all(); +} + #endif /* _ASM_RISCV_TLBFLUSH_H */ diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 478d6763a01a..5bd96f6c8f19 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -1231,6 +1231,10 @@ void __init misc_mem_init(void) early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); arch_numa_init(); sparse_init(); +#ifdef CONFIG_SPARSEMEM_VMEMMAP + /* The entire VMEMMAP region has been propulated. Flush TLB for this region */ + local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END); +#endif zone_sizes_init(); reserve_crashkernel(); memblock_dump_all(); @@ -1240,6 +1244,7 @@ void __init misc_mem_init(void) int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, struct vmem_altmap *altmap) { + /* Defer the required TLB flush until the entire VMEMMAP region has been populated */ return vmemmap_populate_basepages(start, end, node, NULL); } #endif
The spare_init() calls memmap_populate() many times to create VA to PA mapping for the VMEMMAP area, where all "strcut page" are located once CONFIG_SPARSEMEM_VMEMMAP is defined. These "struct page" are later initialized in the zone_sizes_init() function. However, during this process, no sfence.vma instruction is executed for this VMEMMAP area. This omission may cause the hart to fail to perform page table work because some data related to the address translation is invisible to the hart. To solve this issue, the local_flush_tlb_kernel_range() is called right after the spare_init() to execute a sfence.vma instruction for the VMEMMAP area, ensuring that all data related to the address translation is visible to the hart. Fixes: d95f1a542c3d ("RISC-V: Implement sparsemem") Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> --- arch/riscv/include/asm/tlbflush.h | 7 +++++++ arch/riscv/mm/init.c | 5 +++++ 2 files changed, 12 insertions(+)