Mike Frysinger 04e4f2b18c FDPIC: Respect PT_GNU_STACK exec protection markings when creating NOMMU stack ... The current code will load the stack size and protection markings, but then only use the markings in the MMU code path. The NOMMU code path always passes PROT_EXEC to the mmap() call. While this doesn't matter to most people whilst the code is running, it will cause a pointless icache flush when starting every FDPIC application. Typically this icache flush will be of a region on the order of 128KB in size, or may be the entire icache, depending on the facilities available on the CPU. In the case where the arch default behaviour seems to be desired (EXSTACK_DEFAULT), we probe VM_STACK_FLAGS for VM_EXEC to determine whether we should be setting PROT_EXEC or not. For arches that support an MPU (Memory Protection Unit - an MMU without the virtual mapping capability), setting PROT_EXEC or not will make an important difference. It should be noted that this change also affects the executability of the brk region, since ELF-FDPIC has that share with the stack. However, this is probably irrelevant as NOMMU programs aren't likely to use the brk region, preferring instead allocation via mmap(). Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2010-01-06 18:16:02 -08:00
..
asm-offsets.h	kbuild: move asm-offsets.h to include/generated	2009-12-12 13:08:14 +01:00
atomic.h
auxvec.h
ax88796.h
bitops.h
bitsperlong.h
bug.h
bugs.h
busctl-regs.h
byteorder.h
cache.h
cacheflush.h	block: add helpers to run flush_dcache_page() against a bio and a request's pages	2009-11-26 09:16:19 +01:00
checksum.h
cpu-irqs.h
cpumask.h
cputime.h
current.h
delay.h
device.h
div64.h
dm9000.h
dma-mapping.h
dma.h
elf.h	elf: kill USE_ELF_CORE_DUMP	2009-12-16 07:20:12 -08:00
emergency-restart.h
errno.h
fb.h
fcntl.h
fpu.h
ftrace.h
futex.h
gdb-stub.h	misc: remove redundant start_kernel prototypes	2009-09-23 10:05:22 -07:00
gpio-regs.h
hardirq.h	FRV: Use asm/generic-hardirq.h	2009-09-23 10:15:21 -07:00
highmem.h
hw_irq.h
io.h
ioctl.h
ioctls.h
ipcbuf.h
irc-regs.h
irq_regs.h
irq.h
Kbuild
kdebug.h
kmap_types.h
linkage.h
local.h
math-emu.h
mb-regs.h
mb86943a.h
mb93091-fpga-irqs.h
mb93093-fpga-irqs.h
mb93493-irqs.h
mb93493-regs.h
mc146818rtc.h
mem-layout.h
mman.h	mm: remove duplicate asm/mman.h files	2009-09-22 07:17:42 -07:00
mmu_context.h
mmu.h
module.h
msgbuf.h
mutex.h
page.h	FDPIC: Respect PT_GNU_STACK exec protection markings when creating NOMMU stack	2010-01-06 18:16:02 -08:00
param.h
pci.h
percpu.h
perf_event.h	perf: Do the big rename: Performance Counters -> Performance Events	2009-09-21 14:28:04 +02:00
pgalloc.h
pgtable.h
poll.h
posix_types.h
processor.h
ptrace.h
registers.h
resource.h
scatterlist.h
sections.h
segment.h
sembuf.h
serial-regs.h
serial.h
setup.h
shmbuf.h
shmparam.h
sigcontext.h
siginfo.h
signal.h
smp.h
socket.h	net: Generalize socket rx gap / receive queue overflow cmsg	2009-10-12 13:26:31 -07:00
sockios.h
spinlock.h
spr-regs.h
stat.h
statfs.h
string.h
suspend.h
swab.h
syscall.h
system.h
termbits.h
termios.h
thread_info.h
timer-regs.h
timex.h
tlb.h
tlbflush.h
topology.h
types.h
uaccess.h
ucontext.h
unaligned.h
unistd.h	perf: Do the big rename: Performance Counters -> Performance Events	2009-09-21 14:28:04 +02:00
user.h
vga.h
virtconvert.h
xor.h