From 24a5da73f49c17ca88f369b257fef620a494e79d Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Fri, 1 Feb 2008 17:49:41 +0100 Subject: [PATCH] x86_64: make bootmap_start page align v6 boot oopses when a system has 64 or 128 GB of RAM installed: Calling initcall 0xffffffff80bc33b6: sctp_init+0x0/0x711() BUG: unable to handle kernel NULL pointer dereference at 000000000000005f IP: [] proc_register+0xe7/0x10f PGD 0 Oops: 0000 [1] SMP CPU 0 Modules linked in: Pid: 1, comm: swapper Not tainted 2.6.24-smp-g5a514e21-dirty #6 RIP: 0010:[] [] proc_register+0xe7/0x10f RSP: 0000:ffff810824c57e60 EFLAGS: 00010246 RAX: 000000000000d7d7 RBX: ffff811024c5fa80 RCX: ffff810824c57e08 RDX: 0000000000000000 RSI: 0000000000000195 RDI: ffffffff80cc2460 RBP: ffffffffffffffff R08: 0000000000000000 R09: ffff811024c5fa80 R10: 0000000000000000 R11: 0000000000000002 R12: ffff810824c57e6c R13: 0000000000000000 R14: ffff810824c57ee0 R15: 00000006abd25bee FS: 0000000000000000(0000) GS:ffffffff80b4d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b CR2: 000000000000005f CR3: 0000000000201000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process swapper (pid: 1, threadinfo ffff810824c56000, task ffff812024c52000) Stack: ffffffff80a57348 0000019500000000 ffff811024c5fa80 0000000000000000 00000000ffffff97 ffffffff802bfef0 0000000000000000 ffffffffffffffff 0000000000000000 ffffffff80bc3b4b ffff810824c57ee0 ffffffff80bc34a5 Call Trace: [] ? create_proc_entry+0x73/0x8a [] ? sctp_snmp_proc_init+0x1c/0x34 [] ? sctp_init+0xef/0x711 [] ? kernel_init+0x175/0x2e1 [] ? child_rip+0xa/0x12 [] ? kernel_init+0x0/0x2e1 [] ? child_rip+0x0/0x12 Code: 1e 48 83 7b 38 00 75 08 48 c7 43 38 f0 e8 82 80 48 83 7b 30 00 75 08 48 c7 43 30 d0 e9 82 80 48 c7 c7 60 24 cc 80 e8 bd 5a 54 00 <48> 8b 45 60 48 89 6b 58 48 89 5d 60 48 89 43 50 fe 05 f5 25 a0 RIP [] proc_register+0xe7/0x10f RSP CR2: 000000000000005f ---[ end trace 02c2d78def82877a ]--- Kernel panic - not syncing: Attempted to kill init! it turns out some variables near end of bss are corrupted already. in System.map we have ffffffff80d40420 b rsi_table ffffffff80d40620 B krb5_seq_lock ffffffff80d40628 b i.20437 ffffffff80d40630 b xprt_rdma_inline_write_padding ffffffff80d40638 b sunrpc_table_header ffffffff80d40640 b zero ffffffff80d40644 b min_memreg ffffffff80d40648 b rpcrdma_tk_lock_g ffffffff80d40650 B sctp_assocs_id_lock ffffffff80d40658 B proc_net_sctp ffffffff80d40660 B sctp_assocs_id ffffffff80d40680 B sysctl_sctp_mem ffffffff80d40690 B sysctl_sctp_rmem ffffffff80d406a0 B sysctl_sctp_wmem ffffffff80d406b0 b sctp_ctl_socket ffffffff80d406b8 b sctp_pf_inet6_specific ffffffff80d406c0 b sctp_pf_inet_specific ffffffff80d406c8 b sctp_af_v4_specific ffffffff80d406d0 b sctp_af_v6_specific ffffffff80d406d8 b sctp_rand.33270 ffffffff80d406dc b sctp_memory_pressure ffffffff80d406e0 b sctp_sockets_allocated ffffffff80d406e4 b sctp_memory_allocated ffffffff80d406e8 b sctp_sysctl_header ffffffff80d406f0 b zero ffffffff80d406f4 A __bss_stop ffffffff80d406f4 A _end and setup_node_bootmem() will use that page 0xd40000 for bootmap Bootmem setup node 0 0000000000000000-0000000828000000 NODE_DATA [000000000008a485 - 0000000000091484] bootmap [0000000000d406f4 - 0000000000e456f3] pages 105 Bootmem setup node 1 0000000828000000-0000001028000000 NODE_DATA [0000000828000000 - 0000000828006fff] bootmap [0000000828007000 - 0000000828106fff] pages 100 Bootmem setup node 2 0000001028000000-0000001828000000 NODE_DATA [0000001028000000 - 0000001028006fff] bootmap [0000001028007000 - 0000001028106fff] pages 100 Bootmem setup node 3 0000001828000000-0000002028000000 NODE_DATA [0000001828000000 - 0000001828006fff] bootmap [0000001828007000 - 0000001828106fff] pages 100 setup_node_bootmem() makes NODE_DATA cacheline aligned, and bootmap is page-aligned. the patch updates find_e820_area() to make sure we can meet the alignment constraints. Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar --- arch/x86/kernel/e820_64.c | 8 +++++--- arch/x86/kernel/setup_64.c | 3 ++- arch/x86/mm/init_64.c | 13 ++++--------- arch/x86/mm/numa_64.c | 35 ++++++++++++++++++++--------------- include/asm-x86/e820_64.h | 2 +- 5 files changed, 32 insertions(+), 29 deletions(-) diff --git a/arch/x86/kernel/e820_64.c b/arch/x86/kernel/e820_64.c index b74e83b214cc..9f65b4cc323c 100644 --- a/arch/x86/kernel/e820_64.c +++ b/arch/x86/kernel/e820_64.c @@ -171,12 +171,13 @@ int __init e820_all_mapped(unsigned long start, unsigned long end, } /* - * Find a free area in a specific range. + * Find a free area with specified alignment in a specific range. */ unsigned long __init find_e820_area(unsigned long start, unsigned long end, - unsigned size) + unsigned size, unsigned long align) { int i; + unsigned long mask = ~(align - 1); for (i = 0; i < e820.nr_map; i++) { struct e820entry *ei = &e820.map[i]; @@ -190,7 +191,8 @@ unsigned long __init find_e820_area(unsigned long start, unsigned long end, continue; while (bad_addr(&addr, size) && addr+size <= ei->addr+ei->size) ; - last = PAGE_ALIGN(addr) + size; + addr = (addr + align - 1) & mask; + last = addr + size; if (last > ei->addr + ei->size) continue; if (last > end) diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c index 77fb87bf6e5a..18df70c534b9 100644 --- a/arch/x86/kernel/setup_64.c +++ b/arch/x86/kernel/setup_64.c @@ -182,7 +182,8 @@ contig_initmem_init(unsigned long start_pfn, unsigned long end_pfn) unsigned long bootmap_size, bootmap; bootmap_size = bootmem_bootmap_pages(end_pfn)<> PAGE_SHIFT, end_pfn); diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 9a471be4f5f1..eabcaed76c28 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -354,17 +354,10 @@ static void __init find_early_table_space(unsigned long end) * need roughly 0.5KB per GB. */ start = 0x8000; - table_start = find_e820_area(start, end, tables); + table_start = find_e820_area(start, end, tables, PAGE_SIZE); if (table_start == -1UL) panic("Cannot find space for the kernel page tables"); - /* - * When you have a lot of RAM like 256GB, early_table will not fit - * into 0x8000 range, find_e820_area() will find area after kernel - * bss but the table_start is not page aligned, so need to round it - * up to avoid overlap with bss: - */ - table_start = round_up(table_start, PAGE_SIZE); table_start >>= PAGE_SHIFT; table_end = table_start; @@ -420,7 +413,9 @@ void __init_refok init_memory_mapping(unsigned long start, unsigned long end) mmu_cr4_features = read_cr4(); __flush_tlb_all(); - reserve_early(table_start << PAGE_SHIFT, table_end << PAGE_SHIFT, "PGTABLE"); + if (!after_bootmem) + reserve_early(table_start << PAGE_SHIFT, + table_end << PAGE_SHIFT, "PGTABLE"); } #ifndef CONFIG_NUMA diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c index d33954866085..9f533deb9dad 100644 --- a/arch/x86/mm/numa_64.c +++ b/arch/x86/mm/numa_64.c @@ -84,25 +84,23 @@ static int __init populate_memnodemap(const struct bootnode *nodes, static int __init allocate_cachealigned_memnodemap(void) { - unsigned long pad, pad_addr; + unsigned long addr; memnodemap = memnode.embedded_map; if (memnodemapsize <= ARRAY_SIZE(memnode.embedded_map)) return 0; - pad = L1_CACHE_BYTES - 1; - pad_addr = 0x8000; - nodemap_size = pad + sizeof(s16) * memnodemapsize; - nodemap_addr = find_e820_area(pad_addr, end_pfn<> PAGE_SHIFT; end_pfn = end >> PAGE_SHIFT; - node_data[nodeid] = early_node_mem(nodeid, start, end, pgdat_size); + node_data[nodeid] = early_node_mem(nodeid, start, end, pgdat_size, + SMP_CACHE_BYTES); if (node_data[nodeid] == NULL) return; nodedata_phys = __pa(node_data[nodeid]); @@ -211,8 +212,12 @@ void __init setup_node_bootmem(int nodeid, unsigned long start, /* Find a place for the bootmem map */ bootmap_pages = bootmem_bootmap_pages(end_pfn - start_pfn); bootmap_start = round_up(nodedata_phys + pgdat_size, PAGE_SIZE); + /* + * SMP_CAHCE_BYTES could be enough, but init_bootmem_node like + * to use that to align to PAGE_SIZE + */ bootmap = early_node_mem(nodeid, bootmap_start, end, - bootmap_pages<= end) free_bootmem((unsigned long)node_data[nodeid], diff --git a/include/asm-x86/e820_64.h b/include/asm-x86/e820_64.h index cc0946996055..a560c4f5d500 100644 --- a/include/asm-x86/e820_64.h +++ b/include/asm-x86/e820_64.h @@ -15,7 +15,7 @@ #ifndef __ASSEMBLY__ extern unsigned long find_e820_area(unsigned long start, unsigned long end, - unsigned size); + unsigned size, unsigned long align); extern void add_memory_region(unsigned long start, unsigned long size, int type); extern void setup_memory_region(void); -- 2.39.5