linux/arch/x86
Yinghai Lu 752bea4abb x86: reserve dma32 early for gart
a system with 256 GB of RAM, when NUMA is disabled crashes the
following way:

Your BIOS doesn't leave a aperture memory hole
Please enable the IOMMU option in the BIOS setup
This costs you 64 MB of RAM
Cannot allocate aperture memory hole (ffff8101c0000000,65536K)
Kernel panic - not syncing: Not enough memory for aperture
Pid: 0, comm: swapper Not tainted 2.6.25-rc4-x86-latest.git #33

Call Trace:
 [<ffffffff84037c62>] panic+0xb2/0x190
 [<ffffffff840381fc>] ? release_console_sem+0x7c/0x250
 [<ffffffff847b1628>] ? __alloc_bootmem_nopanic+0x48/0x90
 [<ffffffff847b0ac9>] ? free_bootmem+0x29/0x50
 [<ffffffff847ac1f7>] gart_iommu_hole_init+0x5e7/0x680
 [<ffffffff847b255b>] ? alloc_large_system_hash+0x16b/0x310
 [<ffffffff84506a2f>] ? _etext+0x0/0x1
 [<ffffffff847a2e8c>] pci_iommu_alloc+0x1c/0x40
 [<ffffffff847ac795>] mem_init+0x45/0x1a0
 [<ffffffff8479ff35>] start_kernel+0x295/0x380
 [<ffffffff8479f1c2>] _sinittext+0x1c2/0x230

the root cause is : memmap PMD is too big,
[ffffe200e0600000-ffffe200e07fffff] PMD ->ffff81383c000000 on node 0
almost near 4G..., and vmemmap_alloc_block will use up the ram under 4G.

solution will be:
1. make memmap allocation get memory above 4G...
2. reserve some dma32 range early before we try to set up memmap for all.
and release that before pci_iommu_alloc, so gart or swiotlb could get some
range under 4g limit for sure.

the patch is using method 2.
because method1 may need more code to handle SPARSEMEM and SPASEMEM_VMEMMAP

will get
Your BIOS doesn't leave a aperture memory hole
Please enable the IOMMU option in the BIOS setup
This costs you 64 MB of RAM
Mapping aperture over 65536 KB of RAM @ 4000000
Memory: 264245736k/268959744k available (8484k kernel code, 4187464k reserved, 4004k data, 724k init)

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-19 19:19:55 +02:00
..
boot x86: cleanup: change _end to end_before_pgt 2008-04-19 19:19:55 +02:00
configs x86, core: remove CONFIG_FORCED_INLINING 2008-02-09 23:24:09 +01:00
crypto [CRYPTO] twofish: Merge common glue code 2008-01-14 17:07:57 +11:00
ia32 x86: sys32_execve PT_DTRACE 2008-04-17 17:41:13 +02:00
kernel x86: reserve dma32 early for gart 2008-04-19 19:19:55 +02:00
kvm KVM: MMU: Fix memory leak on guest demand faults 2008-03-25 10:22:17 +02:00
lguest x86: replace remaining __FUNCTION__ occurances 2008-04-17 17:40:57 +02:00
lib Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86 2008-04-18 08:25:51 -07:00
mach-default spelling fixes: arch/i386/ 2007-10-20 01:13:56 +02:00
mach-es7000 i386: es7000 minor cleanups 2007-10-17 20:16:15 +02:00
mach-generic x86: coding style fixes to arch/x86/mach-generic/bigsmp.c 2008-04-17 17:40:48 +02:00
mach-rdc321x x86, rdc321x: remove watchdog file 2008-04-17 17:40:50 +02:00
mach-visws x86: remove pointless comments 2008-04-19 19:19:54 +02:00
mach-voyager x86: remove pointless comments 2008-04-19 19:19:54 +02:00
math-emu x86, fpu: split FPU state from task struct - v5 2008-04-19 19:19:55 +02:00
mm srat, x86: add support for nodes spanning other nodes 2008-04-19 19:19:55 +02:00
oprofile x86: coding style fixes to arch/x86/oprofile/nmi_timer_int.c 2008-04-17 17:40:50 +02:00
pci x86: PAT bug fix for attribute type check after reserve_memtype 2008-04-17 17:41:20 +02:00
power x86: coding style fixes to arch/x86/power/cpu_32.c 2008-04-17 17:40:50 +02:00
vdso x86 vDSO: compile with -g, 64-bit 2008-04-19 19:19:55 +02:00
video x86: remove pointless comments 2008-04-19 19:19:54 +02:00
xen x86: change naming of cpu_initialized_mask for xen 2008-04-17 17:41:32 +02:00
Kconfig srat, x86: add support for nodes spanning other nodes 2008-04-19 19:19:55 +02:00
Kconfig.cpu x86: MPSC should use P6 NOPs 2008-04-17 17:41:34 +02:00
Kconfig.debug x86: 4kstacks default 2008-04-17 17:41:34 +02:00
Makefile x86: add subarch support (for headers) to x86_64 2008-04-17 17:41:01 +02:00
Makefile_32.cpu x86: move i386 and x86_64 Makefiles to arch/x86 2007-10-25 22:27:34 +02:00