linux/arch
Jeremy Fitzhardinge 35c7422649 [PATCH] x86: deflate stack usage in lib/inflate.c
inflate_fixed and huft_build together use around 2.7k of stack.  When
using 4k stacks, I saw stack overflows from interrupts arriving while
unpacking the root initrd:

do_IRQ: stack overflow: 384
 [<c0106b64>] show_trace_log_lvl+0x1a/0x30
 [<c01075e6>] show_trace+0x12/0x14
 [<c010763f>] dump_stack+0x16/0x18
 [<c0107ca4>] do_IRQ+0x6d/0xd9
 [<c010202b>] xen_evtchn_do_upcall+0x6e/0xa2
 [<c0106781>] xen_hypervisor_callback+0x25/0x2c
 [<c010116c>] xen_restore_fl+0x27/0x29
 [<c0330f63>] _spin_unlock_irqrestore+0x4a/0x50
 [<c0117aab>] change_page_attr+0x577/0x584
 [<c0117b45>] kernel_map_pages+0x8d/0xb4
 [<c016a314>] cache_alloc_refill+0x53f/0x632
 [<c016a6c2>] __kmalloc+0xc1/0x10d
 [<c0463d34>] malloc+0x10/0x12
 [<c04641c1>] huft_build+0x2a7/0x5fa
 [<c04645a5>] inflate_fixed+0x91/0x136
 [<c04657e2>] unpack_to_rootfs+0x5f2/0x8c1
 [<c0465acf>] populate_rootfs+0x1e/0xe4

(This was under Xen, but there's no reason it couldn't happen on bare
  hardware.)

This patch mallocs the local variables, thereby reducing the stack
usage to sane levels.

Also, up the heap size for the kernel decompressor to deal with the
extra allocation.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Tim Yamin <plasmaroo@gentoo.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
2007-05-02 19:27:15 +02:00
..
alpha [PATCH] x86: deflate stack usage in lib/inflate.c 2007-05-02 19:27:15 +02:00
arm [PATCH] x86: deflate stack usage in lib/inflate.c 2007-05-02 19:27:15 +02:00
arm26 [PATCH] x86: deflate stack usage in lib/inflate.c 2007-05-02 19:27:15 +02:00
avr32
cris
frv
h8300
i386 [PATCH] x86: deflate stack usage in lib/inflate.c 2007-05-02 19:27:15 +02:00
ia64
m32r
m68k
m68knommu
mips
parisc
powerpc
ppc
s390
sh
sh64
sparc
sparc64
um
v850
x86_64 [PATCH] x86: deflate stack usage in lib/inflate.c 2007-05-02 19:27:15 +02:00
xtensa