linux/arch/x86
Yinghai Lu c729de8fce x86, kdump: Set crashkernel_low automatically
Chao said that kdump does does work well on his system on 3.8
without extra parameter, even iommu does not work with kdump.
And now have to append crashkernel_low=Y in first kernel to make
kdump work.

We have now modified crashkernel=X to allocate memory beyong 4G (if
available) and do not allocate low range for crashkernel if the user
does not specify that with crashkernel_low=Y.  This causes regression
if iommu is not enabled.  Without iommu, swiotlb needs to be setup in
first 4G and there is no low memory available to second kernel.

Set crashkernel_low automatically if the user does not specify that.

For system that does support IOMMU with kdump properly, user could
specify crashkernel_low=0 to save that 72M low ram.

-v3: add swiotlb_size() according to Konrad.
-v4: add comments what 8M is for according to hpa.
     also update more crashkernel_low= in kernel-parameters.txt
-v5: update changelog according to Vivek.
-v6: Change description about swiotlb referring according to HATAYAMA.

Reported-by: WANG Chao <chaowang@redhat.com>
Tested-by: WANG Chao <chaowang@redhat.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1366089828-19692-2-git-send-email-yinghai@kernel.org
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-17 12:35:32 -07:00
..
boot x86: Fix rebuild with EFI_STUB enabled 2013-04-05 13:59:23 -07:00
configs x86: Default to ARCH=x86 to avoid overriding CONFIG_64BIT 2012-12-20 14:37:18 -08:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2013-02-25 15:56:15 -08:00
ia32 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2013-03-02 08:34:06 -08:00
include Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-04-14 11:13:24 -07:00
kernel x86, kdump: Set crashkernel_low automatically 2013-04-17 12:35:32 -07:00
kvm KVM: Allow cross page reads and writes from cached translations. 2013-04-07 13:05:35 +03:00
lguest x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metal 2013-04-10 11:25:10 -07:00
lib x86-64: Fix the failure case in copy_user_handle_tail() 2013-03-18 11:32:03 -07:00
math-emu
mm Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-04-14 11:13:24 -07:00
net x86: bpf_jit_comp: add pkt_type support 2013-01-30 22:38:34 -05:00
oprofile oprofile, x86: Fix wrapping bug in op_x86_get_ctrl() 2012-10-15 14:38:24 +02:00
pci Bug-fixes: 2013-03-03 14:22:53 -08:00
platform Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-02-27 16:17:42 -08:00
power perf,x86: fix kernel crash with PEBS/BTS after suspend/resume 2013-03-15 09:26:35 -07:00
realmode Merge remote-tracking branch 'origin/x86/mm' into x86/mm2 2013-02-01 02:28:36 -08:00
syscalls fix compat truncate/ftruncate 2013-02-25 09:24:55 -05:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-02-05 07:57:09 +11:00
um Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2013-02-23 18:50:11 -08:00
vdso timers/x86/hpet: Use HPET_COUNTER to specify the hpet counter in vread_hpet() 2013-02-15 12:13:18 +01:00
video
xen Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-04-14 11:13:24 -07:00
.gitignore
Kbuild
Kconfig Select VIRT_TO_BUS directly where needed 2013-03-12 11:16:40 -07:00
Kconfig.cpu x86, 386 removal: Document Nx586 as a 386 and thus unsupported 2012-11-29 13:28:39 -08:00
Kconfig.debug
Makefile Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-02-19 19:12:03 -08:00
Makefile_32.cpu x86, 386 removal: Remove CONFIG_M386 from Kconfig 2012-11-29 13:23:01 -08:00
Makefile.um