mirror of https://github.com/torvalds/linux.git
-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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| .. | ||
| xenbus | ||
| xenfs | ||
| Kconfig | ||
| Makefile | ||
| balloon.c | ||
| cpu_hotplug.c | ||
| events.c | ||
| evtchn.c | ||
| features.c | ||
| grant-table.c | ||
| manage.c | ||
| sys-hypervisor.c | ||
| xencomm.c | ||