2005-05-13 15:49:50

by Paweł Sikora

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Subject: [2.6.8] OOPS and SIGSEGV on altivec instruction on PowerPC 7540.

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Hi,

simple runtime altivec detection from userspace causes an oops
on the `vand` instruction. kernel was built *without* CONFIG_ALTIVEC.
i think kernel should return a SIGILL instead of an oops ;-)

Oops: kernel access of bad area, sig: 11 [#65]
NIP: C0008B84 LR: C0007F2C SP: CF373F20 REGS: cf373e70 TRAP: 0300 Not tainted
MSR: 00009032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11
DAR: 00000088, DSISR: 40000000
TASK = c81e04f0[12983] 'altivec' THREAD: cf372000Last syscall: 174
GPR00: C0007F2C CF373F20 C81E04F0 00000004 00000004 00030001 00000000 0FEE08D0
GPR08: 0000F932 C0007F2C 00009032 C0350000 081E0788 00000000 00000000 100A37D8
GPR16: 100A0000 00000000 100A0000 00000000 10070000 100A37C8 100AEF08 00000000
GPR24: 100A1108 00000000 100A59A8 3002AEF8 3002BB80 3002AE60 0FFEA6FC 00000004
Call trace: [c0007f2c]


processor       : 0
cpu             : 7450
clock           : 700MHz
revision        : 2.1 (pvr 8000 0201)
bogomips        : 696.32
machine         : PowerMac4,4
motherboard     : PowerMac4,4 MacRISC2 MacRISC Power Macintosh
detected as     : 80 (eMac)
pmac flags      : 00000001
L2 cache        : 256K unified
memory          : 384MB
pmac-generation : NewWorld

--
The only thing necessary for the triumph of evil
is for good men to do nothing.
- Edmund Burke

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2005-05-13 16:03:54

by Kumar Gala

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Subject: Re: [2.6.8] OOPS and SIGSEGV on altivec instruction on PowerPC 7540.

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This is odd. the 2.6.8 kernel should have the code that causes a SIGILL
if !CONFIG_ALTIVEC. Can you enable CONFIG_KALLSYMS.

- kumar

On May 13, 2005, at 10:49 AM, Pawel Sikora wrote:

> Hi,
>
> simple runtime altivec detection from userspace causes an oops
> on the `vand` instruction. kernel was built *without* CONFIG_ALTIVEC.
> i think kernel should return a SIGILL instead of an oops ;-)
>
> Oops: kernel access of bad area, sig: 11 [#65]
> NIP: C0008B84 LR: C0007F2C SP: CF373F20 REGS: cf373e70 TRAP: 0300 Not
> tainted
> MSR: 00009032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11
> DAR: 00000088, DSISR: 40000000
> TASK = c81e04f0[12983] 'altivec' THREAD: cf372000Last syscall: 174
> GPR00: C0007F2C CF373F20 C81E04F0 00000004 00000004 00030001 00000000
> 0FEE08D0
> GPR08: 0000F932 C0007F2C 00009032 C0350000 081E0788 00000000 00000000
> 100A37D8
> GPR16: 100A0000 00000000 100A0000 00000000 10070000 100A37C8 100AEF08
> 00000000
> GPR24: 100A1108 00000000 100A59A8 3002AEF8 3002BB80 3002AE60 0FFEA6FC
> 00000004
> Call trace: [c0007f2c]
>
>
>
> processor ? ? ? : 0
> cpu ? ? ? ? ? ? : 7450
> clock ? ? ? ? ? : 700MHz
> revision ? ? ? ?: 2.1 (pvr 8000 0201)
> bogomips ? ? ? ?: 696.32
> machine ? ? ? ? : PowerMac4,4
> motherboard ? ? : PowerMac4,4 MacRISC2 MacRISC Power Macintosh
> detected as ? ? : 80 (eMac)
> pmac flags ? ? ?: 00000001
> L2 cache ? ? ? ?: 256K unified
> memory ? ? ? ? ?: 384MB
> pmac-generation : NewWorld
>
> --
> The only thing necessary for the triumph of evil
> ? is for good men to do nothing.
> ?????????????????????????????????????????? - Edmund Burke
> <altivec.c>