http://bugs.freedesktop.org/show_bug.cgi?id=20593 Summary: radeonhd driver generates unaligned traps on Alpha Product: xorg Version: git Platform: Alpha OS/Version: Linux (All) Status: NEW Severity: minor Priority: low Component: Driver/radeonhd AssignedTo: lverhaegen@suse.de ReportedBy: mcree@orcon.net.nz QAContact: xorg-team@lists.x.org CC: mcree@orcon.net.nz The radeonhd driver generates unaligned traps on Alpha architecture. These are not a show stopper, but do incur very inefficient memory accesses via kernel traps, and pollute the kernel logs with annoying messages. Using radeonhd at git df71658688e47614a3f660c28ac1dc77970eb491 But the version is irrelevant as the misaligned memory accesses have been there for a long time - I have been too lazy to report them until now.
From dmesg:
X(2015): unaligned trap at 0000020000903088: 000002000098c5d7 28 1 X(2015): unaligned trap at 0000020000903088: 000002000098c5df 28 1 X(2015): unaligned trap at 0000020000903088: 000002000098c5e7 28 1 X(2015): unaligned trap at 0000020000903088: 0000020000989771 28 1 Connecting gdb to the running X process reveals the culprit: (gdb) list *0x0000020000903088 0x20000903088 is in GetParametersDirect32 (AtomBios/CD_Operations.c:441). 436 } 437 438 UINT32 GetParametersDirect32(PARSER_TEMP_DATA STACK_BASED * pParserTempData) 439 { 440 pParserTempData->CD_Mask.SrcAlignment=alignmentDword; 441 pParserTempData->Index=*(UINT32*)pParserTempData->pWorkingTableData->IP; 442 pParserTempData->pWorkingTableData->IP+=sizeof(UINT32); 443 return pParserTempData->Index; 444 } 445 Line 441 is a 32bit (long word) access. The address dereferenced is not aligned to a 32bit boundary for an unaligned trap to occur. The ati driver is worse. It coughs up unaligned traps from GetParametersDirect16() and GetParametersRegister() too, but I haven't seen these from radeonhd. Cheers Michael. -- Configure bugmail: http://bugs.freedesktop.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the QA contact for the bug. _______________________________________________ xorg-team mailing list xorg-team@lists.x.org http://lists.x.org/mailman/listinfo/xorg-team -- To unsubscribe, e-mail: radeonhd+unsubscribe@opensuse.org For additional commands, e-mail: radeonhd+help@opensuse.org