site_archiver@lists.apple.com Delivered-To: darwin-kernel@lists.apple.com On Tuesday, January 17, 2006, at 02:38PM, James Reynolds <james123@scl.utah.edu> wrote: What, precisely are you trying to figure out? This particular panic was, as it states, due to an alignment error. The instruction in question is likely trying to do a word-aligned operation and the address it's trying to read from, 0x1bcbeae, certainly isn't word-aligned. For example, the MPC7450 user's manual gives these possible causes: * The operand of a floating-point load or store is not word-aligned. * The operand of lmw, stmw, lwarx, or stwcx. is not word-aligned. * The operand of dcbz is in a page that is write-through or cache-inhibited. * An attempt is made to execute dcbz when the data cache is disabled or locked. * An eciwx or ecowx is not word-aligned * A multiple or string access is attempted with MSR[LE] set * In 60x bus mode, an access caused by stvx, stvxl, lvx, or lvxl instruction to a cache-inhibited page, write-through page, disabled L1 cache, or if all ways of the cache are locked. * In 60x bus mode, an access caused by cache-inhibited AltiVec loads, stores, and write-through stores. The 60x bus mode does not support 16-byte bus transactions. Note this requires a re-write of the alignment exception routines in software that supports AltiVec quad-word access in 60x bus mode on the MPC7450. Similar causes would apply to other PPC CPUs. The question then becomes WHY the code in question is trying to operate on an unaligned address, and it's usually either because of a software error or because something has stomped on the memory location or register that contained the address. William Kucharski kucharsk@mac.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.a... This email sent to site_archiver@lists.apple.com