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Diffstat (limited to 'arch/x86/kernel/hw_breakpoint.c')
-rw-r--r--arch/x86/kernel/hw_breakpoint.c40
1 files changed, 14 insertions, 26 deletions
diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c
index 05d5fec64a94..dca2802c666f 100644
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -212,25 +212,6 @@ static int arch_check_va_in_kernelspace(unsigned long va, u8 hbp_len)
212 return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE); 212 return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE);
213} 213}
214 214
215/*
216 * Store a breakpoint's encoded address, length, and type.
217 */
218static int arch_store_info(struct perf_event *bp)
219{
220 struct arch_hw_breakpoint *info = counter_arch_bp(bp);
221 /*
222 * For kernel-addresses, either the address or symbol name can be
223 * specified.
224 */
225 if (info->name)
226 info->address = (unsigned long)
227 kallsyms_lookup_name(info->name);
228 if (info->address)
229 return 0;
230
231 return -EINVAL;
232}
233
234int arch_bp_generic_fields(int x86_len, int x86_type, 215int arch_bp_generic_fields(int x86_len, int x86_type,
235 int *gen_len, int *gen_type) 216 int *gen_len, int *gen_type)
236{ 217{
@@ -362,10 +343,13 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp,
362 return ret; 343 return ret;
363 } 344 }
364 345
365 ret = arch_store_info(bp); 346 /*
366 347 * For kernel-addresses, either the address or symbol name can be
367 if (ret < 0) 348 * specified.
368 return ret; 349 */
350 if (info->name)
351 info->address = (unsigned long)
352 kallsyms_lookup_name(info->name);
369 /* 353 /*
370 * Check that the low-order bits of the address are appropriate 354 * Check that the low-order bits of the address are appropriate
371 * for the alignment implied by len. 355 * for the alignment implied by len.
@@ -502,8 +486,6 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args)
502 rcu_read_lock(); 486 rcu_read_lock();
503 487
504 bp = per_cpu(bp_per_reg[i], cpu); 488 bp = per_cpu(bp_per_reg[i], cpu);
505 if (bp)
506 rc = NOTIFY_DONE;
507 /* 489 /*
508 * Reset the 'i'th TRAP bit in dr6 to denote completion of 490 * Reset the 'i'th TRAP bit in dr6 to denote completion of
509 * exception handling 491 * exception handling
@@ -522,7 +504,13 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args)
522 504
523 rcu_read_unlock(); 505 rcu_read_unlock();
524 } 506 }
525 if (dr6 & (~DR_TRAP_BITS)) 507 /*
508 * Further processing in do_debug() is needed for a) user-space
509 * breakpoints (to generate signals) and b) when the system has
510 * taken exception due to multiple causes
511 */
512 if ((current->thread.debugreg6 & DR_TRAP_BITS) ||
513 (dr6 & (~DR_TRAP_BITS)))
526 rc = NOTIFY_DONE; 514 rc = NOTIFY_DONE;
527 515
528 set_debugreg(dr7, 7); 516 set_debugreg(dr7, 7);