Hoi Peter, On Tue, Feb 19, 2019 at 11:35 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > Generic mmu_gather provides everything SH needs (range tracking and > cache coherency). > > Cc: Will Deacon <will.deacon@xxxxxxx> > Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Nick Piggin <npiggin@xxxxxxxxx> > Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> > Cc: Rich Felker <dalias@xxxxxxxx> > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> I got remote access to an SH7722-based Migo-R again, which spews a long sequence of BUGs during userspace startup. I've bisected this to commit c5b27a889da92f4a ("sh/tlb: Convert SH to generic mmu_gather"). Do you have a clue? Thanks! mount: mounting none on /dev failed: No such device BUG: Bad page state in process grep pfn:0e8c1 page:8fb50820 count:0 mapcount:2 mapping:8f403480 index:0x0 (null) flags: 0xc000000() raw: 0c000000 00000100 00000200 8f403480 00000000 00000000 00000001 00000000 page dumped because: non-NULL mapping CPU: 0 PID: 765 Comm: grep Tainted: G W 5.1.0-rc3-migor-00024-gc5b27a889da92f4a #31 Stack: (0x8e8a7d4c to 0x8e8a8000) 7d40: 8c072e90 8fb50820 8fbf400c 00000000 8c0734bc 7d60: 00000200 8fbf4010 00000001 00000002 8fbf4000 00000002 8fbf400c 8e8a7d9c 7d80: 0030f231 00000100 8e8a7da0 00000000 8c2a8a38 8c2a8c0c 8c2a8a94 8c339fa0 7da0: 8fb052a4 8fb052a4 9165dc07 8c0744ea 00000010 00000000 8c0027ac 00000000 7dc0: 8c073ad0 8e8a7df8 8fb054a0 8fb50980 8c07ab54 000000aa 00000011 8e8b52b4 7de0: 00010000 000000aa 8c2a8a38 8fb50820 8c0027ac 00000000 8fb50824 8fb054a4 7e00: 9165dc07 8c0928e0 8c210e48 8c28900c 8e8a7ecc 8e8a7ee4 8c07a958 00000000 7e20: 8e8b5000 8c09296e 8e8a7ed4 8c08f414 8c28900c 8e8a7e60 8e8a7ecc 00000000 7e40: 9165dc07 8c099d08 8ef16178 8c339f60 00000001 00000000 8c0950bc 8c0027ac 7e60: 8c08b00e 7ba1bfff 40000000 7ba1c000 00000000 7ba1bfff 00000000 ffffffff 7e80: 8c08b1ec 8ef16140 8c08ae58 00000000 8ef16140 7b9fb000 8c094fe4 9165dc07 7ea0: 8c0929e6 8e8a7ecc 00000001 8e8a7ecc 8c092b3e 00100000 00000001 8e8a7ecc 7ec0: 8c090cfe 00000000 8ef16020 8f4b78e0 ffffffff ffffffff 8fb50501 00000001 7ee0: 8e8b5000 8e8b5000 00000000 00000008 8fb74f80 8fb74fa0 8fb74f00 8fb74f20 7f00: 8fb74f40 8fb74f60 8fb76c00 8fb76c20 9165dc07 8c0128a2 00000000 00000000 7f20: 8f4b7918 8f4b78e0 00000000 8f4b78e0 8c016326 8ea34f00 8ea3503c 8ea34f00 7f40: 8ea351bc 00000000 8ea3503c 8ea3507c 8c297c1c 8f4a717c 8f4f37a0 9165dc07 7f60: 8c016a58 7ba1bbe4 00000000 00000000 00000000 8eedd720 8eedd6e0 00000000 7f80: 8c016ac6 00000000 00000071 00000100 8c016abc 8c006242 00000000 00427b38 7fa0: 004c025c 00000000 00427b38 004c025c 000000fc 00000000 000000fc fffff000 7fc0: 00000000 00098d9c 00000000 004ac6f4 7ba1be94 00000000 00000000 7ba1bbe4 7fe0: 7ba1bbe4 00427b4e 0040a978 00000101 004c5450 00000022 ffffd000 00000044 Call trace: [<(ptrval)>] free_pcppages_bulk+0x114/0x33c [<(ptrval)>] free_unref_page_list+0xae/0x10c [<(ptrval)>] arch_local_irq_restore+0x0/0x24 [<(ptrval)>] free_unref_page_commit.isra.24+0x0/0x74 [<(ptrval)>] release_pages+0x1fc/0x2d0 [<(ptrval)>] arch_local_irq_restore+0x0/0x24 [<(ptrval)>] tlb_flush_mmu_free+0x30/0x4c [<(ptrval)>] down_read+0x0/0xc [<(ptrval)>] release_pages+0x0/0x2d0 [<(ptrval)>] tlb_flush_mmu+0x72/0xc0 [<(ptrval)>] remove_vma+0x0/0x48 [<(ptrval)>] kmem_cache_free+0x34/0x90 [<(ptrval)>] unlink_anon_vmas+0xd8/0x150 [<(ptrval)>] arch_local_irq_restore+0x0/0x24 [<(ptrval)>] free_pgd_range+0x1b6/0x324 [<(ptrval)>] free_pgtables+0x70/0xb4 [<(ptrval)>] free_pgd_range+0x0/0x324 [<(ptrval)>] unlink_anon_vmas+0x0/0x150 [<(ptrval)>] arch_tlb_finish_mmu+0x2a/0x74 [<(ptrval)>] tlb_finish_mmu+0x1a/0x38 [<(ptrval)>] exit_mmap+0xa2/0x16c [<(ptrval)>] mmput+0x2a/0x80 [<(ptrval)>] do_exit+0x186/0x85c [<(ptrval)>] do_group_exit+0x2c/0x90 [<(ptrval)>] sys_exit_group+0xa/0x10 [<(ptrval)>] sys_exit_group+0x0/0x10 [<(ptrval)>] syscall_call+0x18/0x1e Disabling lock debugging due to kernel taint BUG: Bad page state in process rcS pfn:0ee78 page:8fb5bf00 count:0 mapcount:2 mapping:8f403480 index:0x0 (null) flags: 0xc000000() raw: 0c000000 00000100 00000200 8f403480 00000000 00000000 00000001 00000000 page dumped because: non-NULL mapping CPU: 0 PID: 763 Comm: rcS Tainted: G B W 5.1.0-rc3-migor-00024-gc5b27a889da92f4a #31 Stack: (0x8ef55e54 to 0x8ef56000) 5e40: 8c072e90 8fb5bf00 8fbf400c 5e60: 00000000 8c0734bc 00000200 8fbf4010 00000001 00000002 8fbf4000 00000002 5e80: 8fbf400c 00989680 0030f231 00000100 8ef55ea8 00000000 8c2a8a38 00000028 5ea0: 00000000 8c29d340 8fb05344 8fb05344 b362ad67 8c074416 8f4f38e0 8c0027ac 5ec0: 8e9125e0 00000000 00000000 8c0027ac 8fb50760 8c0a59e4 8e9125a0 00000180 5ee0: 00000010 8c0a5a9a 8f4a69e0 8f01ad00 8f4f38e0 8f01b21c 8e9125a0 8c09f526 5f00: 8f414cf0 8f01b120 8f4f38e0 8c0281e0 8c20f7dc 8f4a6cdc 00000000 8f4a6cec 5f20: 8c003c18 00401f80 004c6aa0 00000000 8ef55fa4 8ef55fa4 09000080 8c28900c 5f40: 00000000 b362ad67 8c00bbde 8ef55fe4 8f4b7aa0 00000001 09000000 8f4a6c1c 5f60: 004c6ab4 00000055 8c215f8c ffff8bce 00000004 00000009 00003f10 8f4f38e0 5f80: b362ad67 8c0060f8 00401f80 004c6aa0 00000000 00000000 40000000 00000100 5fa0: 8ef54000 00000000 00000450 00000002 00000006 00000003 00000000 004c6ab4 5fc0: 00000000 7bdf069c 004c61d4 00000003 004c61bc 7bdf0670 004c6aa0 00401f80 5fe0: 7bdf069c 00401f94 0047d1cc 00000001 004c5450 00000043 0000000c 00000044 Call trace: [<(ptrval)>] free_pcppages_bulk+0x114/0x33c [<(ptrval)>] free_unref_page+0x4a/0x70 [<(ptrval)>] arch_local_irq_restore+0x0/0x24 [<(ptrval)>] arch_local_irq_restore+0x0/0x24 [<(ptrval)>] free_pipe_info+0x60/0x84 [<(ptrval)>] pipe_release+0x92/0xb8 [<(ptrval)>] __fput+0x3e/0x120 [<(ptrval)>] task_work_run+0x78/0xa8 [<(ptrval)>] _cond_resched+0x0/0x54 [<(ptrval)>] do_notify_resume+0xd4/0x4c8 [<(ptrval)>] do_page_fault+0xda/0x2a8 [<(ptrval)>] resume_userspace+0x0/0x10 BUG: Bad page state in process rcS pfn:0e8b2 page:8fb50640 count:0 mapcount:1026 mapping:8f403480 index:0x0 (null) flags: 0xc000000() raw: 0c000000 00000100 00000200 8f403480 00000000 00000000 00000401 00000000 page dumped because: non-NULL mapping CPU: 0 PID: 763 Comm: rcS Tainted: G B W 5.1.0-rc3-migor-00024-gc5b27a889da92f4a #31 Stack: (0x8ef55e54 to 0x8ef56000) 5e40: 8c072e90 8fb50640 8fbf400c 5e60: 00000000 8c0734bc 00000200 8fbf4010 00000001 00000001 8fbf4000 00000001 5e80: 8fbf400c 00989680 0030f231 00000100 8ef55ea8 00000000 8c2a8a38 00000028 5ea0: 00000000 8c29d340 8fb05344 8fb05344 b362ad67 8c074416 8f4f38e0 8c0027ac 5ec0: 8e9125e0 00000000 00000000 8c0027ac 8fb50760 8c0a59e4 8e9125a0 00000180 5ee0: 00000010 8c0a5a9a 8f4a69e0 8f01ad00 8f4f38e0 8f01b21c 8e9125a0 8c09f526 5f00: 8f414cf0 8f01b120 8f4f38e0 8c0281e0 8c20f7dc 8f4a6cdc 00000000 8f4a6cec 5f20: 8c003c18 00401f80 004c6aa0 00000000 8ef55fa4 8ef55fa4 09000080 8c28900c 5f40: 00000000 b362ad67 8c00bbde 8ef55fe4 8f4b7aa0 00000001 09000000 8f4a6c1c 5f60: 004c6ab4 00000055 8c215f8c ffff8bce 00000004 00000009 00003f10 8f4f38e0 5f80: b362ad67 8c0060f8 00401f80 004c6aa0 00000000 00000000 40000000 00000100 5fa0: 8ef54000 00000000 00000450 00000002 00000006 00000003 00000000 004c6ab4 5fc0: 00000000 7bdf069c 004c61d4 00000003 004c61bc 7bdf0670 004c6aa0 00401f80 5fe0: 7bdf069c 00401f94 0047d1cc 00000001 004c5450 00000043 0000000c 00000044 Call trace: [<(ptrval)>] free_pcppages_bulk+0x114/0x33c [<(ptrval)>] free_unref_page+0x4a/0x70 [<(ptrval)>] arch_local_irq_restore+0x0/0x24 [<(ptrval)>] arch_local_irq_restore+0x0/0x24 [<(ptrval)>] free_pipe_info+0x60/0x84 [<(ptrval)>] pipe_release+0x92/0xb8 [<(ptrval)>] __fput+0x3e/0x120 [<(ptrval)>] task_work_run+0x78/0xa8 [<(ptrval)>] _cond_resched+0x0/0x54 [<(ptrval)>] do_notify_resume+0xd4/0x4c8 [<(ptrval)>] do_page_fault+0xda/0x2a8 [<(ptrval)>] resume_userspace+0x0/0x10 ... > --- > arch/sh/include/asm/pgalloc.h | 7 ++ > arch/sh/include/asm/tlb.h | 130 ------------------------------------------ > 2 files changed, 8 insertions(+), 129 deletions(-) > > --- a/arch/sh/include/asm/pgalloc.h > +++ b/arch/sh/include/asm/pgalloc.h > @@ -72,6 +72,15 @@ do { \ > tlb_remove_page((tlb), (pte)); \ > } while (0) > > +#if CONFIG_PGTABLE_LEVELS > 2 > +#define __pmd_free_tlb(tlb, pmdp, addr) \ > +do { \ > + struct page *page = virt_to_page(pmdp); \ > + pgtable_pmd_page_dtor(page); \ > + tlb_remove_page((tlb), page); \ > +} while (0); > +#endif > + > static inline void check_pgt_cache(void) > { > quicklist_trim(QUICK_PT, NULL, 25, 16); > --- a/arch/sh/include/asm/tlb.h > +++ b/arch/sh/include/asm/tlb.h > @@ -11,131 +11,8 @@ > > #ifdef CONFIG_MMU > #include <linux/swap.h> > -#include <asm/pgalloc.h> > -#include <asm/tlbflush.h> > -#include <asm/mmu_context.h> > - > -/* > - * TLB handling. This allows us to remove pages from the page > - * tables, and efficiently handle the TLB issues. > - */ > -struct mmu_gather { > - struct mm_struct *mm; > - unsigned int fullmm; > - unsigned long start, end; > -}; > > -static inline void init_tlb_gather(struct mmu_gather *tlb) > -{ > - tlb->start = TASK_SIZE; > - tlb->end = 0; > - > - if (tlb->fullmm) { > - tlb->start = 0; > - tlb->end = TASK_SIZE; > - } > -} > - > -static inline void > -arch_tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, > - unsigned long start, unsigned long end) > -{ > - tlb->mm = mm; > - tlb->start = start; > - tlb->end = end; > - tlb->fullmm = !(start | (end+1)); > - > - init_tlb_gather(tlb); > -} > - > -static inline void > -arch_tlb_finish_mmu(struct mmu_gather *tlb, > - unsigned long start, unsigned long end, bool force) > -{ > - if (tlb->fullmm || force) > - flush_tlb_mm(tlb->mm); > - > - /* keep the page table cache within bounds */ > - check_pgt_cache(); > -} > - > -static inline void > -tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, unsigned long address) > -{ > - if (tlb->start > address) > - tlb->start = address; > - if (tlb->end < address + PAGE_SIZE) > - tlb->end = address + PAGE_SIZE; > -} > - > -#define tlb_remove_huge_tlb_entry(h, tlb, ptep, address) \ > - tlb_remove_tlb_entry(tlb, ptep, address) > - > -/* > - * In the case of tlb vma handling, we can optimise these away in the > - * case where we're doing a full MM flush. When we're doing a munmap, > - * the vmas are adjusted to only cover the region to be torn down. > - */ > -static inline void > -tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma) > -{ > - if (!tlb->fullmm) > - flush_cache_range(vma, vma->vm_start, vma->vm_end); > -} > - > -static inline void > -tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma) > -{ > - if (!tlb->fullmm && tlb->end) { > - flush_tlb_range(vma, tlb->start, tlb->end); > - init_tlb_gather(tlb); > - } > -} > - > -static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) > -{ > -} > - > -static inline void tlb_flush_mmu_free(struct mmu_gather *tlb) > -{ > -} > - > -static inline void tlb_flush_mmu(struct mmu_gather *tlb) > -{ > -} > - > -static inline int __tlb_remove_page(struct mmu_gather *tlb, struct page *page) > -{ > - free_page_and_swap_cache(page); > - return false; /* avoid calling tlb_flush_mmu */ > -} > - > -static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page) > -{ > - __tlb_remove_page(tlb, page); > -} > - > -static inline bool __tlb_remove_page_size(struct mmu_gather *tlb, > - struct page *page, int page_size) > -{ > - return __tlb_remove_page(tlb, page); > -} > - > -static inline void tlb_remove_page_size(struct mmu_gather *tlb, > - struct page *page, int page_size) > -{ > - return tlb_remove_page(tlb, page); > -} > - > -static inline void tlb_change_page_size(struct mmu_gather *tlb, unsigned int page_size) > -{ > -} > - > -#define pte_free_tlb(tlb, ptep, addr) pte_free((tlb)->mm, ptep) > -#define pmd_free_tlb(tlb, pmdp, addr) pmd_free((tlb)->mm, pmdp) > -#define pud_free_tlb(tlb, pudp, addr) pud_free((tlb)->mm, pudp) > - > -#define tlb_migrate_finish(mm) do { } while (0) > +#include <asm-generic/tlb.h> > > #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SUPERH64) > extern void tlb_wire_entry(struct vm_area_struct *, unsigned long, pte_t); > @@ -155,11 +32,6 @@ static inline void tlb_unwire_entry(void > > #else /* CONFIG_MMU */ > > -#define tlb_start_vma(tlb, vma) do { } while (0) > -#define tlb_end_vma(tlb, vma) do { } while (0) > -#define __tlb_remove_tlb_entry(tlb, pte, address) do { } while (0) > -#define tlb_flush(tlb) do { } while (0) > - > #include <asm-generic/tlb.h> > > #endif /* CONFIG_MMU */ Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds