> $ dmesg | grep unaligned > init(1): unaligned access to 0x600000000008b0bb, ip=0x40000000000e3581 I've been looking at this some more and found out more details on what is happening here. These "init" messages actually come from "nash" on the initrd. The specific code in nash is probe_fat() (from libblkid) which is trying to determine if a partition contains a fat/vfat filesystem. The code here accesses unaligned 2-byte objects (the ms_sectors field of msdos_super_block, and vs_sectors/vs_dir_entries fields of vfat_super_block structures). The reason these generate unaligned traps in some kernels but not others is the the PSR.ac bit is set differently in the different kernels ... apparently because there is no explicit initialization of it (that I can see[1]) so it inherits a value from some random place. Why this scheduler patch consistently results in PSR.ac being set is still a mystery to me ... but we should pick some spot to initialize it. -Tony [1] The only initialization I can find is in the ia32 exec path in binfmt_elf32.c ... which is obviously of little use for nash, which is a 64-bit native ia64 binary. -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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