tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 48bbaf8b793e0770798519f8ee1ea2908ff0943a commit: 23f8c1823bd4041064ab557283dbb37657549c5b [2357/3551] arch: add do_page_fault prototypes config: alpha-randconfig-r112-20231127 (https://download.01.org/0day-ci/archive/20231127/202311272143.1EnibyIf-lkp@xxxxxxxxx/config) compiler: alpha-linux-gcc (GCC) 13.2.0 reproduce: (https://download.01.org/0day-ci/archive/20231127/202311272143.1EnibyIf-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202311272143.1EnibyIf-lkp@xxxxxxxxx/ sparse warnings: (new ones prefixed by >>) >> arch/alpha/mm/fault.c:193:60: sparse: sparse: Using plain integer as NULL pointer vim +193 arch/alpha/mm/fault.c ^1da177e4c3f41 Linus Torvalds 2005-04-16 56 ^1da177e4c3f41 Linus Torvalds 2005-04-16 57 ^1da177e4c3f41 Linus Torvalds 2005-04-16 58 /* ^1da177e4c3f41 Linus Torvalds 2005-04-16 59 * This routine handles page faults. It determines the address, ^1da177e4c3f41 Linus Torvalds 2005-04-16 60 * and the problem, and then passes it off to handle_mm_fault(). ^1da177e4c3f41 Linus Torvalds 2005-04-16 61 * ^1da177e4c3f41 Linus Torvalds 2005-04-16 62 * mmcsr: ^1da177e4c3f41 Linus Torvalds 2005-04-16 63 * 0 = translation not valid ^1da177e4c3f41 Linus Torvalds 2005-04-16 64 * 1 = access violation ^1da177e4c3f41 Linus Torvalds 2005-04-16 65 * 2 = fault-on-read ^1da177e4c3f41 Linus Torvalds 2005-04-16 66 * 3 = fault-on-execute ^1da177e4c3f41 Linus Torvalds 2005-04-16 67 * 4 = fault-on-write ^1da177e4c3f41 Linus Torvalds 2005-04-16 68 * ^1da177e4c3f41 Linus Torvalds 2005-04-16 69 * cause: ^1da177e4c3f41 Linus Torvalds 2005-04-16 70 * -1 = instruction fetch ^1da177e4c3f41 Linus Torvalds 2005-04-16 71 * 0 = load ^1da177e4c3f41 Linus Torvalds 2005-04-16 72 * 1 = store ^1da177e4c3f41 Linus Torvalds 2005-04-16 73 * ^1da177e4c3f41 Linus Torvalds 2005-04-16 74 * Registers $9 through $15 are saved in a block just prior to `regs' and ^1da177e4c3f41 Linus Torvalds 2005-04-16 75 * are saved and restored around the call to allow exception code to ^1da177e4c3f41 Linus Torvalds 2005-04-16 76 * modify them. ^1da177e4c3f41 Linus Torvalds 2005-04-16 77 */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 78 ^1da177e4c3f41 Linus Torvalds 2005-04-16 79 /* Macro for exception fixup code to access integer registers. */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 80 #define dpf_reg(r) \ ^1da177e4c3f41 Linus Torvalds 2005-04-16 81 (((unsigned long *)regs)[(r) <= 8 ? (r) : (r) <= 15 ? (r)-16 : \ 491af60ffb848b Sergei Trofimovich 2018-12-31 82 (r) <= 18 ? (r)+10 : (r)-10]) ^1da177e4c3f41 Linus Torvalds 2005-04-16 83 ^1da177e4c3f41 Linus Torvalds 2005-04-16 84 asmlinkage void ^1da177e4c3f41 Linus Torvalds 2005-04-16 85 do_page_fault(unsigned long address, unsigned long mmcsr, ^1da177e4c3f41 Linus Torvalds 2005-04-16 86 long cause, struct pt_regs *regs) ^1da177e4c3f41 Linus Torvalds 2005-04-16 87 { ^1da177e4c3f41 Linus Torvalds 2005-04-16 88 struct vm_area_struct * vma; ^1da177e4c3f41 Linus Torvalds 2005-04-16 89 struct mm_struct *mm = current->mm; ^1da177e4c3f41 Linus Torvalds 2005-04-16 90 const struct exception_table_entry *fixup; 50a7ca3c6fc869 Souptick Joarder 2018-08-17 91 int si_code = SEGV_MAPERR; 50a7ca3c6fc869 Souptick Joarder 2018-08-17 92 vm_fault_t fault; dde1607248328c Peter Xu 2020-04-01 93 unsigned int flags = FAULT_FLAG_DEFAULT; ^1da177e4c3f41 Linus Torvalds 2005-04-16 94 ^1da177e4c3f41 Linus Torvalds 2005-04-16 95 /* As of EV6, a load into $31/$f31 is a prefetch, and never faults ^1da177e4c3f41 Linus Torvalds 2005-04-16 96 (or is suppressed by the PALcode). Support that for older CPUs ^1da177e4c3f41 Linus Torvalds 2005-04-16 97 by ignoring such an instruction. */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 98 if (cause == 0) { ^1da177e4c3f41 Linus Torvalds 2005-04-16 99 unsigned int insn; ^1da177e4c3f41 Linus Torvalds 2005-04-16 100 __get_user(insn, (unsigned int __user *)regs->pc); ^1da177e4c3f41 Linus Torvalds 2005-04-16 101 if ((insn >> 21 & 0x1f) == 0x1f && ^1da177e4c3f41 Linus Torvalds 2005-04-16 102 /* ldq ldl ldt lds ldg ldf ldwu ldbu */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 103 (1ul << (insn >> 26) & 0x30f00001400ul)) { ^1da177e4c3f41 Linus Torvalds 2005-04-16 104 regs->pc += 4; ^1da177e4c3f41 Linus Torvalds 2005-04-16 105 return; ^1da177e4c3f41 Linus Torvalds 2005-04-16 106 } ^1da177e4c3f41 Linus Torvalds 2005-04-16 107 } ^1da177e4c3f41 Linus Torvalds 2005-04-16 108 ^1da177e4c3f41 Linus Torvalds 2005-04-16 109 /* If we're in an interrupt context, or have no user context, ^1da177e4c3f41 Linus Torvalds 2005-04-16 110 we must not take the fault. */ 70ffdb9393a726 David Hildenbrand 2015-05-11 111 if (!mm || faulthandler_disabled()) ^1da177e4c3f41 Linus Torvalds 2005-04-16 112 goto no_context; ^1da177e4c3f41 Linus Torvalds 2005-04-16 113 ^1da177e4c3f41 Linus Torvalds 2005-04-16 114 #ifdef CONFIG_ALPHA_LARGE_VMALLOC ^1da177e4c3f41 Linus Torvalds 2005-04-16 115 if (address >= TASK_SIZE) ^1da177e4c3f41 Linus Torvalds 2005-04-16 116 goto vmalloc_fault; ^1da177e4c3f41 Linus Torvalds 2005-04-16 117 #endif 759496ba6407c6 Johannes Weiner 2013-09-12 118 if (user_mode(regs)) 759496ba6407c6 Johannes Weiner 2013-09-12 119 flags |= FAULT_FLAG_USER; c0f6eda41f97db Peter Xu 2020-08-11 120 perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); 0bcc426b1defa6 Kautuk Consul 2012-08-19 121 retry: a050ba1e7422f2 Linus Torvalds 2023-06-24 122 vma = lock_mm_and_find_vma(mm, address, regs); ^1da177e4c3f41 Linus Torvalds 2005-04-16 123 if (!vma) a050ba1e7422f2 Linus Torvalds 2023-06-24 124 goto bad_area_nosemaphore; ^1da177e4c3f41 Linus Torvalds 2005-04-16 125 ^1da177e4c3f41 Linus Torvalds 2005-04-16 126 /* Ok, we have a good vm_area for this memory access, so ^1da177e4c3f41 Linus Torvalds 2005-04-16 127 we can handle it. */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 128 si_code = SEGV_ACCERR; ^1da177e4c3f41 Linus Torvalds 2005-04-16 129 if (cause < 0) { ^1da177e4c3f41 Linus Torvalds 2005-04-16 130 if (!(vma->vm_flags & VM_EXEC)) ^1da177e4c3f41 Linus Torvalds 2005-04-16 131 goto bad_area; ^1da177e4c3f41 Linus Torvalds 2005-04-16 132 } else if (!cause) { ^1da177e4c3f41 Linus Torvalds 2005-04-16 133 /* Allow reads even for write-only mappings */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 134 if (!(vma->vm_flags & (VM_READ | VM_WRITE))) ^1da177e4c3f41 Linus Torvalds 2005-04-16 135 goto bad_area; ^1da177e4c3f41 Linus Torvalds 2005-04-16 136 } else { ^1da177e4c3f41 Linus Torvalds 2005-04-16 137 if (!(vma->vm_flags & VM_WRITE)) ^1da177e4c3f41 Linus Torvalds 2005-04-16 138 goto bad_area; 759496ba6407c6 Johannes Weiner 2013-09-12 139 flags |= FAULT_FLAG_WRITE; ^1da177e4c3f41 Linus Torvalds 2005-04-16 140 } ^1da177e4c3f41 Linus Torvalds 2005-04-16 141 ^1da177e4c3f41 Linus Torvalds 2005-04-16 142 /* If for any reason at all we couldn't handle the fault, ^1da177e4c3f41 Linus Torvalds 2005-04-16 143 make sure we exit gracefully rather than endlessly redo ^1da177e4c3f41 Linus Torvalds 2005-04-16 144 the fault. */ c0f6eda41f97db Peter Xu 2020-08-11 145 fault = handle_mm_fault(vma, address, flags, regs); 0bcc426b1defa6 Kautuk Consul 2012-08-19 146 dce45493aff3fd Al Viro 2023-01-30 147 if (fault_signal_pending(fault, regs)) { dce45493aff3fd Al Viro 2023-01-30 148 if (!user_mode(regs)) dce45493aff3fd Al Viro 2023-01-30 149 goto no_context; 0bcc426b1defa6 Kautuk Consul 2012-08-19 150 return; dce45493aff3fd Al Viro 2023-01-30 151 } 0bcc426b1defa6 Kautuk Consul 2012-08-19 152 d92725256b4f22 Peter Xu 2022-05-30 153 /* The fault is fully completed (including releasing mmap lock) */ d92725256b4f22 Peter Xu 2022-05-30 154 if (fault & VM_FAULT_COMPLETED) d92725256b4f22 Peter Xu 2022-05-30 155 return; d92725256b4f22 Peter Xu 2022-05-30 156 83c54070ee1a2d Nicholas Piggin 2007-07-19 157 if (unlikely(fault & VM_FAULT_ERROR)) { 83c54070ee1a2d Nicholas Piggin 2007-07-19 158 if (fault & VM_FAULT_OOM) ^1da177e4c3f41 Linus Torvalds 2005-04-16 159 goto out_of_memory; 33692f27597fca Linus Torvalds 2015-01-29 160 else if (fault & VM_FAULT_SIGSEGV) 33692f27597fca Linus Torvalds 2015-01-29 161 goto bad_area; 83c54070ee1a2d Nicholas Piggin 2007-07-19 162 else if (fault & VM_FAULT_SIGBUS) 83c54070ee1a2d Nicholas Piggin 2007-07-19 163 goto do_sigbus; ^1da177e4c3f41 Linus Torvalds 2005-04-16 164 BUG(); ^1da177e4c3f41 Linus Torvalds 2005-04-16 165 } 0bcc426b1defa6 Kautuk Consul 2012-08-19 166 0bcc426b1defa6 Kautuk Consul 2012-08-19 167 if (fault & VM_FAULT_RETRY) { 4064b982706375 Peter Xu 2020-04-01 168 flags |= FAULT_FLAG_TRIED; 0bcc426b1defa6 Kautuk Consul 2012-08-19 169 3e4e28c5a8f01e Michel Lespinasse 2020-06-08 170 /* No need to mmap_read_unlock(mm) as we would 0bcc426b1defa6 Kautuk Consul 2012-08-19 171 * have already released it in __lock_page_or_retry 0bcc426b1defa6 Kautuk Consul 2012-08-19 172 * in mm/filemap.c. 0bcc426b1defa6 Kautuk Consul 2012-08-19 173 */ 0bcc426b1defa6 Kautuk Consul 2012-08-19 174 0bcc426b1defa6 Kautuk Consul 2012-08-19 175 goto retry; 0bcc426b1defa6 Kautuk Consul 2012-08-19 176 } 0bcc426b1defa6 Kautuk Consul 2012-08-19 177 d8ed45c5dcd455 Michel Lespinasse 2020-06-08 178 mmap_read_unlock(mm); 0bcc426b1defa6 Kautuk Consul 2012-08-19 179 ^1da177e4c3f41 Linus Torvalds 2005-04-16 180 return; ^1da177e4c3f41 Linus Torvalds 2005-04-16 181 ^1da177e4c3f41 Linus Torvalds 2005-04-16 182 /* Something tried to access memory that isn't in our memory map. ^1da177e4c3f41 Linus Torvalds 2005-04-16 183 Fix it, but check if it's kernel or user first. */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 184 bad_area: d8ed45c5dcd455 Michel Lespinasse 2020-06-08 185 mmap_read_unlock(mm); ^1da177e4c3f41 Linus Torvalds 2005-04-16 186 a050ba1e7422f2 Linus Torvalds 2023-06-24 187 bad_area_nosemaphore: ^1da177e4c3f41 Linus Torvalds 2005-04-16 188 if (user_mode(regs)) ^1da177e4c3f41 Linus Torvalds 2005-04-16 189 goto do_sigsegv; ^1da177e4c3f41 Linus Torvalds 2005-04-16 190 ^1da177e4c3f41 Linus Torvalds 2005-04-16 191 no_context: ^1da177e4c3f41 Linus Torvalds 2005-04-16 192 /* Are we prepared to handle this fault as an exception? */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 @193 if ((fixup = search_exception_tables(regs->pc)) != 0) { ^1da177e4c3f41 Linus Torvalds 2005-04-16 194 unsigned long newpc; ^1da177e4c3f41 Linus Torvalds 2005-04-16 195 newpc = fixup_exception(dpf_reg, fixup, regs->pc); ^1da177e4c3f41 Linus Torvalds 2005-04-16 196 regs->pc = newpc; ^1da177e4c3f41 Linus Torvalds 2005-04-16 197 return; ^1da177e4c3f41 Linus Torvalds 2005-04-16 198 } ^1da177e4c3f41 Linus Torvalds 2005-04-16 199 ^1da177e4c3f41 Linus Torvalds 2005-04-16 200 /* Oops. The kernel tried to access some bad page. We'll have to ^1da177e4c3f41 Linus Torvalds 2005-04-16 201 terminate things with extreme prejudice. */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 202 printk(KERN_ALERT "Unable to handle kernel paging request at " ^1da177e4c3f41 Linus Torvalds 2005-04-16 203 "virtual address %016lx\n", address); ^1da177e4c3f41 Linus Torvalds 2005-04-16 204 die_if_kernel("Oops", regs, cause, (unsigned long*)regs - 16); 0e25498f8cd43c Eric W. Biederman 2021-06-28 205 make_task_dead(SIGKILL); ^1da177e4c3f41 Linus Torvalds 2005-04-16 206 ^1da177e4c3f41 Linus Torvalds 2005-04-16 207 /* We ran out of memory, or some other thing happened to us that ^1da177e4c3f41 Linus Torvalds 2005-04-16 208 made us unable to handle the page fault gracefully. */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 209 out_of_memory: d8ed45c5dcd455 Michel Lespinasse 2020-06-08 210 mmap_read_unlock(mm); ^1da177e4c3f41 Linus Torvalds 2005-04-16 211 if (!user_mode(regs)) ^1da177e4c3f41 Linus Torvalds 2005-04-16 212 goto no_context; 1cb3d8e2c8d30d Nicholas Piggin 2010-04-29 213 pagefault_out_of_memory(); 1cb3d8e2c8d30d Nicholas Piggin 2010-04-29 214 return; ^1da177e4c3f41 Linus Torvalds 2005-04-16 215 ^1da177e4c3f41 Linus Torvalds 2005-04-16 216 do_sigbus: d8ed45c5dcd455 Michel Lespinasse 2020-06-08 217 mmap_read_unlock(mm); ^1da177e4c3f41 Linus Torvalds 2005-04-16 218 /* Send a sigbus, regardless of whether we were in kernel ^1da177e4c3f41 Linus Torvalds 2005-04-16 219 or user mode. */ 7de5f68d497cbc Eric W. Biederman 2021-05-28 220 force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *) address); ^1da177e4c3f41 Linus Torvalds 2005-04-16 221 if (!user_mode(regs)) ^1da177e4c3f41 Linus Torvalds 2005-04-16 222 goto no_context; ^1da177e4c3f41 Linus Torvalds 2005-04-16 223 return; ^1da177e4c3f41 Linus Torvalds 2005-04-16 224 ^1da177e4c3f41 Linus Torvalds 2005-04-16 225 do_sigsegv: 7de5f68d497cbc Eric W. Biederman 2021-05-28 226 force_sig_fault(SIGSEGV, si_code, (void __user *) address); ^1da177e4c3f41 Linus Torvalds 2005-04-16 227 return; ^1da177e4c3f41 Linus Torvalds 2005-04-16 228 :::::: The code at line 193 was first introduced by commit :::::: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Linux-2.6.12-rc2 :::::: TO: Linus Torvalds <torvalds@xxxxxxxxxxxxxxx> :::::: CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxx> -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
