On Tue, Aug 30, 2016 at 11:17:07PM +0300, Anatoly Pugachev wrote: > On Tue, Aug 30, 2016 at 10:16 PM, Theodore Ts'o <tytso@xxxxxxx> wrote: > > On Tue, Aug 30, 2016 at 06:12:39PM +0300, Anatoly Pugachev wrote: > >> > >> (gdb) p bh->b_data > >> $1 = "\300;9\230\000\000\000\005\000\000\253\204\000\000\000\070\000\000\000\000\000\000$\022\000\000\000\000\000\000$<\000\000\000\000\000\000$\270\000\000\000\000\000\000$]\000\000\000\000\000\000$\024", > >> '\000' <repeats 967 times> > >> (gdb) p offset > >> $2 = 16 > >> (gdb) p *bh->b_data > >> $3 = -64 '\300' > >> (gdb) p *(bh->b_data+offset) > >> $6 = 0 '\000' > > > > Can you give us "p &bh->b_data" (so we can get the starting address of > > b_data to make sure it's aligned) and "p offset" (so we can check and > > make sure offset is sane)? > > (gdb) p &bh->b_data > $7 = (char (*)[1024]) 0x2e9b9c > (gdb) p offset > $8 = 16 AFAICT, each bh is malloc'd via e2fsck_allocate_memory and nothing seems to guarantee that the char b_data[1024] will be aligned to a multiple of 8 (it certainly isn't on x64), so I guess this isn't much of a surprise. We could change b_data to a pointer and then posix_memalign it. --D > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
