Bug 15014
| Summary: | DDB can't find symbol for address in kernel loadable modules. | ||
|---|---|---|---|
| Product: | Base System | Reporter: | Vladimir N.Silyaev <vns> |
| Component: | kern | Assignee: | freebsd-bugs (Nobody) <bugs> |
| Status: | Closed FIXED | ||
| Severity: | Affects Only Me | ||
| Priority: | Normal | ||
| Version: | 4.0-CURRENT | ||
| Hardware: | Any | ||
| OS: | Any | ||
State Changed From-To: open->closed Suggested changes applied and adapted for the link_aout.c code, revs: 1.22 +7 -5 src/sys/kern/link_elf.c 1.23 +7 -5 src/sys/kern/link_aout.c 1.17.2.2 +7 -5 src/sys/kern/link_aout.c 1.11.2.2 +7 -5 src/sys/kern/link_elf.c (The last two being -stable). Thanks! Responsible Changed From-To: freebsd-bugs->pgollucci I will take it Responsible Changed From-To: pgollucci->freebsd-bugs fat fingered the pr # |
DDB can't locate names to stack frame, when frames include pointer from kernel loadable module Fix: Apply the following patch. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- After applying this patch, in the same circumstance, trace will be printing: db> trace linux_open(c4324280,c45f3f80,28051dc6,3,28054a10) at linux_open syscall(2f,2f,2f,28054a10,3) at syscall+0x119 Xint0x80_syscall() at Xint0x80_syscall+0x26 P.S. It's looks like that the /sys/kern/link_aout.c have the same kind of problem.--DwhcW3yPVfRLJaH6h0lqgbR6Je9Lx6w7LJR4CBVZJdmweEAU Content-Type: text/plain; name="file.diff" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="file.diff" --- /sys/kern/link_elf.c.orig Fri Oct 29 18:12:02 1999 +++ /sys/kern/link_elf.c Sat Nov 20 17:51:16 1999 @@ -958,17 +958,19 @@ const Elf_Sym* es; const Elf_Sym* best = 0; int i; + u_long st_value; for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) { if (es->st_name == 0) continue; - if (off >= es->st_value) { - if (off - es->st_value < diff) { - diff = off - es->st_value; + st_value = es->st_value + (u_long)ef->address; + if (off >= st_value) { + if (off - st_value < diff) { + diff = off - st_value; best = es; if (diff == 0) break; - } else if (off - es->st_value == diff) { + } else if (off - st_value == diff) { best = es; } } -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- How-To-Repeat: - Build kernel with DDB support. - Load linux KLD (launch linux command). Throw to DDB, then db> b linux_open db> c Run any linux command, for example: > /compat/linux/bin/bash Breakpoint at linux_open: pushl %ebp db> trace _end(c4324280,c45f3f80,28051dc6,3,28054a10) at 0xc06ef344 syscall(2f,2f,2f,28054a10,3) at syscall+0x119 Xint0x80_syscall() at Xint0x80_syscall+0x26 db> c