577eebeae3
-fstack-protector uses a special per-cpu "stack canary" value. gcc generates special code in each function to test the canary to make sure that the function's stack hasn't been overrun. On x86-64, this is simply an offset of %gs, which is the usual per-cpu base segment register, so setting it up simply requires loading %gs's base as normal. On i386, the stack protector segment is %gs (rather than the usual kernel percpu %fs segment register). This requires setting up the full kernel GDT and then loading %gs accordingly. We also need to make sure %gs is initialized when bringing up secondary cpus too. To keep things consistent, we do the full GDT/segment register setup on both architectures. Because we need to avoid -fstack-protected code before setting up the GDT and because there's no way to disable it on a per-function basis, several files need to have stack-protector inhibited. [ Impact: allow Xen booting with stack-protector enabled ] Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> |
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| .. | ||
| kmemcheck | ||
| Makefile | ||
| dump_pagetables.c | ||
| extable.c | ||
| fault.c | ||
| gup.c | ||
| highmem_32.c | ||
| hugetlbpage.c | ||
| init.c | ||
| init_32.c | ||
| init_64.c | ||
| iomap_32.c | ||
| ioremap.c | ||
| k8topology_64.c | ||
| kmmio.c | ||
| memtest.c | ||
| mmap.c | ||
| mmio-mod.c | ||
| numa.c | ||
| numa_32.c | ||
| numa_64.c | ||
| pageattr-test.c | ||
| pageattr.c | ||
| pat.c | ||
| pf_in.c | ||
| pf_in.h | ||
| pgtable.c | ||
| pgtable_32.c | ||
| srat_32.c | ||
| srat_64.c | ||
| testmmiotrace.c | ||
| tlb.c | ||