| Message ID | 20230803062404.2373480-1-rppt@kernel.org (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | parisc/mm: preallocate fixmap page tables at init | expand |
On 8/3/23 08:24, Mike Rapoport wrote: > From: "Mike Rapoport (IBM)" <rppt@kernel.org> > > Christoph Biedl reported early OOM on recent kernels: > > swapper: page allocation failure: order:0, mode:0x100(__GFP_ZERO), > nodemask=(null) > CPU: 0 PID: 0 Comm: swapper Not tainted 6.3.0-rc4+ #16 > Hardware name: 9000/785/C3600 > Backtrace: > [<10408594>] show_stack+0x48/0x5c > [<10e152d8>] dump_stack_lvl+0x48/0x64 > [<10e15318>] dump_stack+0x24/0x34 > [<105cf7f8>] warn_alloc+0x10c/0x1c8 > [<105d068c>] __alloc_pages+0xbbc/0xcf8 > [<105d0e4c>] __get_free_pages+0x28/0x78 > [<105ad10c>] __pte_alloc_kernel+0x30/0x98 > [<10406934>] set_fixmap+0xec/0xf4 > [<10411ad4>] patch_map.constprop.0+0xa8/0xdc > [<10411bb0>] __patch_text_multiple+0xa8/0x208 > [<10411d78>] patch_text+0x30/0x48 > [<1041246c>] arch_jump_label_transform+0x90/0xcc > [<1056f734>] jump_label_update+0xd4/0x184 > [<1056fc9c>] static_key_enable_cpuslocked+0xc0/0x110 > [<1056fd08>] static_key_enable+0x1c/0x2c > [<1011362c>] init_mem_debugging_and_hardening+0xdc/0xf8 > [<1010141c>] start_kernel+0x5f0/0xa98 > [<10105da8>] start_parisc+0xb8/0xe4 > ... > Kernel Fault: Code=15 (Data TLB miss fault) at addr 0f7fe3c0 > CPU: 0 PID: 0 Comm: swapper Not tainted 6.3.0-rc4+ #16 > Hardware name: 9000/785/C3600 > > This happens because patching static key code temporarily maps it via > fixmap and if it happens before page allocator is initialized set_fixmap() > cannot allocate memory using pte_alloc_kernel(). > > Make sure that fixmap page tables are preallocated early so that > pte_offset_kernel() in set_fixmap() never resorts to pte allocation. > > Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Now queued up in parisc for-next tree. Thanks to Christoph for bisecting and Mike for coming up with this patch! Helge
On 8/3/23 08:24, Mike Rapoport wrote: > From: "Mike Rapoport (IBM)" <rppt@kernel.org> > > Christoph Biedl reported early OOM on recent kernels: > > swapper: page allocation failure: order:0, mode:0x100(__GFP_ZERO), > nodemask=(null) > CPU: 0 PID: 0 Comm: swapper Not tainted 6.3.0-rc4+ #16 > Hardware name: 9000/785/C3600 > Backtrace: > [<10408594>] show_stack+0x48/0x5c > [<10e152d8>] dump_stack_lvl+0x48/0x64 > [<10e15318>] dump_stack+0x24/0x34 > [<105cf7f8>] warn_alloc+0x10c/0x1c8 > [<105d068c>] __alloc_pages+0xbbc/0xcf8 > [<105d0e4c>] __get_free_pages+0x28/0x78 > [<105ad10c>] __pte_alloc_kernel+0x30/0x98 > [<10406934>] set_fixmap+0xec/0xf4 > [<10411ad4>] patch_map.constprop.0+0xa8/0xdc > [<10411bb0>] __patch_text_multiple+0xa8/0x208 > [<10411d78>] patch_text+0x30/0x48 > [<1041246c>] arch_jump_label_transform+0x90/0xcc > [<1056f734>] jump_label_update+0xd4/0x184 > [<1056fc9c>] static_key_enable_cpuslocked+0xc0/0x110 > [<1056fd08>] static_key_enable+0x1c/0x2c > [<1011362c>] init_mem_debugging_and_hardening+0xdc/0xf8 > [<1010141c>] start_kernel+0x5f0/0xa98 > [<10105da8>] start_parisc+0xb8/0xe4 > > Mem-Info: > active_anon:0 inactive_anon:0 isolated_anon:0 > active_file:0 inactive_file:0 isolated_file:0 > unevictable:0 dirty:0 writeback:0 > slab_reclaimable:0 slab_unreclaimable:0 > mapped:0 shmem:0 pagetables:0 > sec_pagetables:0 bounce:0 > kernel_misc_reclaimable:0 > free:0 free_pcp:0 free_cma:0 > Node 0 active_anon:0kB inactive_anon:0kB active_file:0kB > inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB > mapped:0kB dirty:0kB writeback:0kB shmem:0kB > +writeback_tmp:0kB kernel_stack:0kB pagetables:0kB sec_pagetables:0kB > all_unreclaimable? no > Normal free:0kB boost:0kB min:0kB low:0kB high:0kB > reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB active_file:0kB > inactive_file:0kB unevictable:0kB writepending:0kB > +present:1048576kB managed:1039360kB mlocked:0kB bounce:0kB free_pcp:0kB > local_pcp:0kB free_cma:0kB > lowmem_reserve[]: 0 0 > Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB > 0*1024kB 0*2048kB 0*4096kB = 0kB > 0 total pagecache pages > 0 pages in swap cache > Free swap = 0kB > Total swap = 0kB > 262144 pages RAM > 0 pages HighMem/MovableOnly > 2304 pages reserved > Backtrace: > [<10411d78>] patch_text+0x30/0x48 > [<1041246c>] arch_jump_label_transform+0x90/0xcc > [<1056f734>] jump_label_update+0xd4/0x184 > [<1056fc9c>] static_key_enable_cpuslocked+0xc0/0x110 > [<1056fd08>] static_key_enable+0x1c/0x2c > [<1011362c>] init_mem_debugging_and_hardening+0xdc/0xf8 > [<1010141c>] start_kernel+0x5f0/0xa98 > [<10105da8>] start_parisc+0xb8/0xe4 > > Kernel Fault: Code=15 (Data TLB miss fault) at addr 0f7fe3c0 > CPU: 0 PID: 0 Comm: swapper Not tainted 6.3.0-rc4+ #16 > Hardware name: 9000/785/C3600 > > This happens because patching static key code temporarily maps it via > fixmap and if it happens before page allocator is initialized set_fixmap() > cannot allocate memory using pte_alloc_kernel(). > > Make sure that fixmap page tables are preallocated early so that > pte_offset_kernel() in set_fixmap() never resorts to pte allocation. > > Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Thanks, Mike! > --- > > I didn't add Fixes tag with the commit Christoph bisected because that > commit didn't change anything in the initialization of the static keys > and I really doubt it is the actual cause of the issue. Yeah I also don't see how the commit could cause a static key initialization to happen sooner than it already has. But if it's manifesting for whatever reason since 6.4 then a "Cc: stable # 6.4+" would be in order. > > arch/parisc/mm/fixmap.c | 3 --- > arch/parisc/mm/init.c | 34 ++++++++++++++++++++++++++++++++++ > 2 files changed, 34 insertions(+), 3 deletions(-) > > diff --git a/arch/parisc/mm/fixmap.c b/arch/parisc/mm/fixmap.c > index cc15d737fda6..ae3493dae9dc 100644 > --- a/arch/parisc/mm/fixmap.c > +++ b/arch/parisc/mm/fixmap.c > @@ -19,9 +19,6 @@ void notrace set_fixmap(enum fixed_addresses idx, phys_addr_t phys) > pmd_t *pmd = pmd_offset(pud, vaddr); > pte_t *pte; > > - if (pmd_none(*pmd)) > - pte = pte_alloc_kernel(pmd, vaddr); > - > pte = pte_offset_kernel(pmd, vaddr); > set_pte_at(&init_mm, vaddr, pte, __mk_pte(phys, PAGE_KERNEL_RWX)); > flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE); > diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c > index 406c52fe23d5..389941c7f209 100644 > --- a/arch/parisc/mm/init.c > +++ b/arch/parisc/mm/init.c > @@ -669,6 +669,39 @@ static void __init gateway_init(void) > PAGE_SIZE, PAGE_GATEWAY, 1); > } > > +static void __init fixmap_init(void) > +{ > + unsigned long addr = FIXMAP_START; > + unsigned long end = FIXMAP_START + FIXMAP_SIZE; > + pgd_t *pgd = pgd_offset_k(addr); > + p4d_t *p4d = p4d_offset(pgd, addr); > + pud_t *pud = pud_offset(p4d, addr); > + pmd_t *pmd; > + > + BUILD_BUG_ON(FIXMAP_SIZE > PMD_SIZE); > + > +#if CONFIG_PGTABLE_LEVELS == 3 > + if (pud_none(*pud)) { > + pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER, > + PAGE_SIZE << PMD_TABLE_ORDER); > + if (!pmd) > + panic("fixmap: pmd allocation failed.\n"); > + pud_populate(NULL, pud, pmd); > + } > +#endif > + > + pmd = pmd_offset(pud, addr); > + do { > + pte_t *pte = memblock_alloc(PAGE_SIZE, PAGE_SIZE); > + if (!pte) > + panic("fixmap: pte allocation failed.\n"); > + > + pmd_populate_kernel(&init_mm, pmd, pte); > + > + addr += PAGE_SIZE; > + } while (addr < end); > +} > + > static void __init parisc_bootmem_free(void) > { > unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, }; > @@ -683,6 +716,7 @@ void __init paging_init(void) > setup_bootmem(); > pagetable_init(); > gateway_init(); > + fixmap_init(); > flush_cache_all_local(); /* start with known state */ > flush_tlb_all_local(NULL); > > > base-commit: 5d0c230f1de8c7515b6567d9afba1f196fb4e2f4
On 8/3/23 10:48, Vlastimil Babka wrote: > On 8/3/23 08:24, Mike Rapoport wrote: >> From: "Mike Rapoport (IBM)" <rppt@kernel.org> >> >> Christoph Biedl reported early OOM on recent kernels: >> >> swapper: page allocation failure: order:0, mode:0x100(__GFP_ZERO), >> nodemask=(null) >> CPU: 0 PID: 0 Comm: swapper Not tainted 6.3.0-rc4+ #16 >> Hardware name: 9000/785/C3600 >> Backtrace: >> [<10408594>] show_stack+0x48/0x5c >> [<10e152d8>] dump_stack_lvl+0x48/0x64 >> [<10e15318>] dump_stack+0x24/0x34 >> [<105cf7f8>] warn_alloc+0x10c/0x1c8 >> [<105d068c>] __alloc_pages+0xbbc/0xcf8 >> [<105d0e4c>] __get_free_pages+0x28/0x78 >> [<105ad10c>] __pte_alloc_kernel+0x30/0x98 >> [<10406934>] set_fixmap+0xec/0xf4 >> [<10411ad4>] patch_map.constprop.0+0xa8/0xdc >> [<10411bb0>] __patch_text_multiple+0xa8/0x208 >> [<10411d78>] patch_text+0x30/0x48 >> [<1041246c>] arch_jump_label_transform+0x90/0xcc >> [<1056f734>] jump_label_update+0xd4/0x184 >> [<1056fc9c>] static_key_enable_cpuslocked+0xc0/0x110 >> [<1056fd08>] static_key_enable+0x1c/0x2c >> [<1011362c>] init_mem_debugging_and_hardening+0xdc/0xf8 >> [<1010141c>] start_kernel+0x5f0/0xa98 >> [<10105da8>] start_parisc+0xb8/0xe4 >> >> Mem-Info: >> active_anon:0 inactive_anon:0 isolated_anon:0 >> active_file:0 inactive_file:0 isolated_file:0 >> unevictable:0 dirty:0 writeback:0 >> slab_reclaimable:0 slab_unreclaimable:0 >> mapped:0 shmem:0 pagetables:0 >> sec_pagetables:0 bounce:0 >> kernel_misc_reclaimable:0 >> free:0 free_pcp:0 free_cma:0 >> Node 0 active_anon:0kB inactive_anon:0kB active_file:0kB >> inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB >> mapped:0kB dirty:0kB writeback:0kB shmem:0kB >> +writeback_tmp:0kB kernel_stack:0kB pagetables:0kB sec_pagetables:0kB >> all_unreclaimable? no >> Normal free:0kB boost:0kB min:0kB low:0kB high:0kB >> reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB active_file:0kB >> inactive_file:0kB unevictable:0kB writepending:0kB >> +present:1048576kB managed:1039360kB mlocked:0kB bounce:0kB free_pcp:0kB >> local_pcp:0kB free_cma:0kB >> lowmem_reserve[]: 0 0 >> Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB >> 0*1024kB 0*2048kB 0*4096kB = 0kB >> 0 total pagecache pages >> 0 pages in swap cache >> Free swap = 0kB >> Total swap = 0kB >> 262144 pages RAM >> 0 pages HighMem/MovableOnly >> 2304 pages reserved >> Backtrace: >> [<10411d78>] patch_text+0x30/0x48 >> [<1041246c>] arch_jump_label_transform+0x90/0xcc >> [<1056f734>] jump_label_update+0xd4/0x184 >> [<1056fc9c>] static_key_enable_cpuslocked+0xc0/0x110 >> [<1056fd08>] static_key_enable+0x1c/0x2c >> [<1011362c>] init_mem_debugging_and_hardening+0xdc/0xf8 >> [<1010141c>] start_kernel+0x5f0/0xa98 >> [<10105da8>] start_parisc+0xb8/0xe4 >> >> Kernel Fault: Code=15 (Data TLB miss fault) at addr 0f7fe3c0 >> CPU: 0 PID: 0 Comm: swapper Not tainted 6.3.0-rc4+ #16 >> Hardware name: 9000/785/C3600 >> >> This happens because patching static key code temporarily maps it via >> fixmap and if it happens before page allocator is initialized set_fixmap() >> cannot allocate memory using pte_alloc_kernel(). >> >> Make sure that fixmap page tables are preallocated early so that >> pte_offset_kernel() in set_fixmap() never resorts to pte allocation. >> >> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> > > Acked-by: Vlastimil Babka <vbabka@suse.cz> > > .. > But if it's manifesting for whatever reason since 6.4 then a "Cc: stable # > 6.4+" would be in order. Thanks Vlastimil! I've added your Acked-by and the Cc... Helge
diff --git a/arch/parisc/mm/fixmap.c b/arch/parisc/mm/fixmap.c index cc15d737fda6..ae3493dae9dc 100644 --- a/arch/parisc/mm/fixmap.c +++ b/arch/parisc/mm/fixmap.c @@ -19,9 +19,6 @@ void notrace set_fixmap(enum fixed_addresses idx, phys_addr_t phys) pmd_t *pmd = pmd_offset(pud, vaddr); pte_t *pte; - if (pmd_none(*pmd)) - pte = pte_alloc_kernel(pmd, vaddr); - pte = pte_offset_kernel(pmd, vaddr); set_pte_at(&init_mm, vaddr, pte, __mk_pte(phys, PAGE_KERNEL_RWX)); flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE); diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c index 406c52fe23d5..389941c7f209 100644 --- a/arch/parisc/mm/init.c +++ b/arch/parisc/mm/init.c @@ -669,6 +669,39 @@ static void __init gateway_init(void) PAGE_SIZE, PAGE_GATEWAY, 1); } +static void __init fixmap_init(void) +{ + unsigned long addr = FIXMAP_START; + unsigned long end = FIXMAP_START + FIXMAP_SIZE; + pgd_t *pgd = pgd_offset_k(addr); + p4d_t *p4d = p4d_offset(pgd, addr); + pud_t *pud = pud_offset(p4d, addr); + pmd_t *pmd; + + BUILD_BUG_ON(FIXMAP_SIZE > PMD_SIZE); + +#if CONFIG_PGTABLE_LEVELS == 3 + if (pud_none(*pud)) { + pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER, + PAGE_SIZE << PMD_TABLE_ORDER); + if (!pmd) + panic("fixmap: pmd allocation failed.\n"); + pud_populate(NULL, pud, pmd); + } +#endif + + pmd = pmd_offset(pud, addr); + do { + pte_t *pte = memblock_alloc(PAGE_SIZE, PAGE_SIZE); + if (!pte) + panic("fixmap: pte allocation failed.\n"); + + pmd_populate_kernel(&init_mm, pmd, pte); + + addr += PAGE_SIZE; + } while (addr < end); +} + static void __init parisc_bootmem_free(void) { unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, }; @@ -683,6 +716,7 @@ void __init paging_init(void) setup_bootmem(); pagetable_init(); gateway_init(); + fixmap_init(); flush_cache_all_local(); /* start with known state */ flush_tlb_all_local(NULL);