Bug 6559
| Summary: | Kernel oops with trigonometric functions on a 386 w/o fpu | ||
|---|---|---|---|
| Product: | [Retired] Red Hat Linux | Reporter: | donald |
| Component: | kernel | Assignee: | Michael K. Johnson <johnsonm> |
| Status: | CLOSED CURRENTRELEASE | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 6.0 | ||
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | i386 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2000-01-04 22:27:49 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
The fact that changing the compiler helped _might_ mean it is a compiler problem, but it might not be. Assigned to dledford Assigned to dledford This should be fixed in 2.2.14 and higher |
I'm running RedHat 6.0 on a 386 without a math co-processor. The following code (compiled with 'gcc tst.c -lm' always produces a kernel oops and generates a segmentation fault. (According to 'objdump --disassemble', there are no 486 BSWAP instructions in the executable) #include <stdio.h> #include <math.h> int main() { printf ("%f\n", sin(1.0)); exit (0); } Similar behaviour results with the following perl script... $ perl -e '{ print sin(1.0), "\n" }' Segmentation fault Curiously, though... $ perl -e '{ print sin(3.0), "\n" }' 0.141120008059867 works fine. For what it's worth, here's the oops (sorry about the wrapping). >Unable to handle kernel paging request at virtual address 8214aabf >current->tss.cr3 = 00646000, %cr3 = 00646000 >*pde = 00000000 >Oops: 0000 >CPU: 0 >EIP: 0010:[poly_sine+945/1140] >EFLAGS: 00010296 >eax: 8214aabb ebx: 00000000 ecx: 07781a5c edx: 1de06972 >esi: 8214aabb edi: c03cff00 ebp: c03cff00 esp: c03cfeac >ds: 0018 es: 0018 ss: 0018 >Process perl (pid: 7036, process nr: 30, stackpage=c03cf000) >Stack: 00000000 c03cffb4 c03cfefc c03cfeec c03cfee8 00000000 c03cfed4 c03cfef4 > 8214aabb 2cd09e2b 42d18469 921fb544 c03cffb4 00000000 00000000 0013d0fa > 9c6c0650 1b2cb8ab ab698587 4318c275 53682eaf 12ffb1d5 48677021 d76aa478 >Call Trace: [fsin+71/292] [FPU_trigb+62/76] [math_emulate+2255/2388] > [do_no_page+179/192] [handle_mm_fault+198/352] > [device_not_available+55/60] [ret_from_exception+0/16] > [startup_32+43/286] >Code: f7 60 04 89 54 24 28 8b 54 24 5c 89 54 24 10 89 54 24 2c 89 Some futher notes: Manually upgrading the kernel to 2.2.12 (w/ CONFIG_MATH_EMULATION=y and CONFIG_M386=y) didn't help. However, I tried recompiling the kernel (v2.2.12) using an older compiler (gcc version 2.7.2.3) and that seemed to fix the problem. It looks as though there may be some issues with the C compiler that comes with RedHat 6.0 (egcs-2.91.66 / egcs-1.1.2) and Linux's math emulation.