getcpu is available as a vdso entry and an emulated vsyscall.
Programs that for some reason don't want to use the vdso should
still be able to call getcpu without relying on the slow emulated
vsyscall. It costs almost nothing to expose it as a real syscall.
We also need this for the following patch in vsyscall=native mode.
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/6b19f55bdb06a0c32c2fa6dba9b6f222e1fde999.1312988155.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
As of commit 98d0ac38ca
Author: Andy Lutomirski <luto@mit.edu>
Date: Thu Jul 14 06:47:22 2011 -0400
x86-64: Move vread_tsc and vread_hpet into the vDSO
user code no longer directly calls into code in arch/x86/kernel/, so
we don't need compile flag hacks to make it safe. All vdso code is
in the vdso directory now.
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/835cd05a4c7740544d09723d6ba48f4406f9826c.1312988155.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Three places in the kernel assume that the only long mode CPL 3
selector is __USER_CS. This is not true on Xen -- Xen's sysretq
changes cs to the magic value 0xe033.
Two of the places are corner cases, but as of "x86-64: Improve
vsyscall emulation CS and RIP handling"
(c9712944b2), vsyscalls will segfault
if called with Xen's extra CS selector. This causes a panic when
older init builds die.
It seems impossible to make Xen use __USER_CS reliably without
taking a performance hit on every system call, so this fixes the
tests instead with a new paravirt op. It's a little ugly because
ptrace.h can't include paravirt.h.
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/f4fcb3947340d9e96ce1054a432f183f9da9db83.1312378163.git.luto@mit.edu
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Xen needs to handle VVAR_PAGE, introduced in git commit:
9fd67b4ed0
x86-64: Give vvars their own page
Otherwise we die during bootup with a message like:
(XEN) mm.c:940:d10 Error getting mfn 1888 (pfn 1e3e48) from L1 entry
8000000001888465 for l1e_owner=10, pg_owner=10
(XEN) mm.c:5049:d10 ptwr_emulate: could not get_page_from_l1e()
[ 0.000000] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 0.000000] IP: [<ffffffff8103a930>] xen_set_pte+0x20/0xe0
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/4659478ed2f3480938f96491c2ecbe2b2e113a23.1312378163.git.luto@mit.edu
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Gold has trouble assigning numbers to the location counter inside of
an output section description. The bug was triggered by
9fd67b4ed0, which consolidated all of
the vsyscall sections into a single section. The workaround is IMO
still nicer than the old way of doing it.
This produces an apparently valid kernel image and passes my vdso
tests on both GNU ld version 2.21.51.0.6-2.fc15 20110118 and GNU
gold (version 2.21.51.0.6-2.fc15 20110118) 1.10 as distributed by
Fedora 15.
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/0b260cb806f1f9a25c00ce8377a5f035d57f557a.1312378163.git.luto@mit.edu
Reported-by: Arkadiusz Miskiewicz <a.miskiewicz@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The machinery for __ARCH_HAS_CLOCKSOURCE_DATA assumed a file in
asm-generic would be the default for architectures without their own
file in asm/, but that is not how it works.
Replace it with a Kconfig option instead.
Link: http://lkml.kernel.org/r/4E288AA6.7090804@zytor.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@mit.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Tony Luck <tony.luck@intel.com>
Yet another variant of the Dell Latitude series which requires
reboot=pci.
From the E5420 bug report by Daniel J Blueman:
> The E6420 is affected also (same platform, different casing and
> features), which provides an external confirmation of the issue; I can
> submit a patch for that later or include it if you prefer:
> http://linux.koolsolutions.com/2009/08/04/howto-fix-linux-hangfreeze-during-reboots-and-restarts/
Reported-by: Daniel J Blueman <daniel.blueman@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org>
Rebooting on the Dell E5420 often hangs with the keyboard or ACPI
methods, but is reliable via the PCI method.
[ hpa: this was deferred because we believed for a long time that the
recent reshuffling of the boot priorities in commit
660e34cebf fixed this platform.
Unfortunately that turned out to be incorrect. ]
Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>
Link: http://lkml.kernel.org/r/1305248699-2347-1-git-send-email-daniel.blueman@gmail.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org>
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86. reboot: Make Dell Latitude E6320 use reboot=pci
x86, doc only: Correct real-mode kernel header offset for init_size
x86: Disable AMD_NUMA for 32bit for now
Now that 1b3f2a72bb is in, it is very
important that the below lying comment be removed! :-)
Signed-off-by: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20110718191054.GA18359@liondog.tnic
Acked-by: Andy Lutomirski <luto@mit.edu>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The vread field was bloating struct clocksource everywhere except
x86_64, and I want to change the way this works on x86_64, so let's
split it out into per-arch data.
Cc: x86@kernel.org
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: linux-ia64@vger.kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/3ae5ec76a168eaaae63f08a2a1060b91aa0b7759.1310563276.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Three fixes here:
- Send SIGSEGV if called from compat code or with a funny CS.
- Don't BUG on impossible addresses.
- Add a missing local_irq_disable.
This patch also removes an unused variable.
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/6fb2b13ab39b743d1e4f466eef13425854912f7f.1310563276.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The macro MIN_MEMORY_BLOCK_SIZE is currently defined twice in two .c
files, and I need it in a third one to fix a powerpc bug, so let's
first move it into a header
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Commit 2706a0bf7b ("x86, NUMA: Enable CONFIG_AMD_NUMA on 32bit
too") enabled AMD NUMA for 32bit too. Unfortunately, SPARSEMEM
on 32bit had rather coarse (512MiB) addr->node mapping
granularity due to lack of space in page->flags. This led to
boot failure on certain AMD NUMA machines which had 128MiB
alignment on nodes.
Patches to properly detect this condition and reject NUMA
configuration are posted[1] but deemed too pervasive for merge
at this point (-rc6). Disable AMD NUMA for 32bit for now and
re-enable once the detection logic is merged.
[1] http://thread.gmane.org/gmane.linux.kernel/1161279/focus=1162583
Reported-by: Hans Rosenfeld <hans.rosenfeld@amd.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Conny Seidel <conny.seidel@amd.com>
Link: http://lkml.kernel.org/r/20110711083432.GC943@htj.dyndns.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Don't use the EFI reboot method by default
x86, suspend: Restore MISC_ENABLE MSR in realmode wakeup
x86, reboot: Acer Aspire One A110 reboot quirk
x86-32, NUMA: Fix boot regression caused by NUMA init unification on highmem machines
Previously we would check for acpi_sci_override_gsi == gsi every time
a PCI device was enabled. That works during early bootup, but later
on it could lead to triggering unnecessarily the acpi_gsi_to_irq(..) lookup.
The reason is that acpi_sci_override_gsi was declared in __initdata and
after early bootup could contain bogus values.
This patch moves the check for acpi_sci_override_gsi to the
site where the ACPI SCI is preset.
CC: stable@kernel.org
Reported-by: Raghavendra D Prabhu <rprabhu@wnohang.net>
Tested-by: Raghavendra D Prabhu <rprabhu@wnohang.net>
[http://lists.xensource.com/archives/html/xen-devel/2011-07/msg00154.html]
Suggested-by: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Testing suggests that at least some Lenovos and some Intels will
fail to reboot via EFI, attempting to jump to an unmapped
physical address. In the long run we could handle this by
providing a page table with a 1:1 mapping of physical addresses,
but for now it's probably just easier to assume that ACPI or
legacy methods will be present and reboot via those.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/r/1309985557-15350-1-git-send-email-mjg@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Some BIOSes will reset the Intel MISC_ENABLE MSR (specifically the
XD_DISABLE bit) when resuming from S3, which can interact poorly with
ebba638ae7. In 32bit PAE mode, this can
lead to a fault when EFER is restored by the kernel wakeup routines,
due to it setting the NX bit for a CPU that (thanks to the BIOS reset)
now incorrectly thinks it lacks the NX feature. (64bit is not affected
because it uses a common CPU bring-up that specifically handles the
XD_DISABLE bit.)
The need for MISC_ENABLE being restored so early is specific to the S3
resume path. Normally, MISC_ENABLE is saved in save_processor_state(),
but this happens after the resume header is created, so just reproduce
the logic here. (acpi_suspend_lowlevel() creates the header, calls
do_suspend_lowlevel, which calls save_processor_state(), so the saved
processor context isn't available during resume header creation.)
[ hpa: Consider for stable if OK in mainline ]
Signed-off-by: Kees Cook <kees.cook@canonical.com>
Link: http://lkml.kernel.org/r/20110707011034.GA8523@outflux.net
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: <stable@kernel.org> 2.6.38+
Since git commit
660e34cebf x86: reorder reboot method
preferences,
my Acer Aspire One hangs on reboot. It appears that its ACPI method
for rebooting is broken. The attached patch adds a quirk so that the
machine will reboot via the BIOS.
[ hpa: verified that the ACPI control on this machine is just plain broken. ]
Signed-off-by: Peter Chubb <peter.chubb@nicta.com.au>
Link: http://lkml.kernel.org/r/w439iki5vl.wl%25peter@chubb.wattle.id.au
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* 'stable/bug.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pci: Use the INT_SRC_OVR IRQ (instead of GSI) to preset the ACPI SCI IRQ.
xen/mmu: Fix for linker errors when CONFIG_SMP is not defined.
During 32/64 NUMA init unification, commit 797390d855 ("x86-32,
NUMA: use sparse_memory_present_with_active_regions()") made
32bit mm init call memory_present() automatically from
active_regions instead of leaving it to each NUMA init path.
This commit description is inaccurate - memory_present() calls
aren't the same for flat and numaq. After the commit,
memory_present() is only called for the intersection of e820 and
NUMA layout. Before, on flatmem, memory_present() would be
called from 0 to max_pfn. After, it would be called only on the
areas that e820 indicates to be populated.
This is how x86_64 works and should be okay as memmap is allowed
to contain holes; however, x86_32 DISCONTIGMEM is missing
early_pfn_valid(), which makes memmap_init_zone() assume that
memmap doesn't contain any hole. This leads to the following
oops if e820 map contains holes as it often does on machine with
near or more 4GiB of memory by calling pfn_to_page() on a pfn
which isn't mapped to a NUMA node, a reported by Conny Seidel:
BUG: unable to handle kernel paging request at 000012b0
IP: [<c1aa13ce>] memmap_init_zone+0x6c/0xf2
*pdpt =3D 0000000000000000 *pde =3D f000eef3f000ee00
Oops: 0000 [#1] SMP
last sysfs file:
Modules linked in:
Pid: 0, comm: swapper Not tainted 2.6.39-rc5-00164-g797390d #1 To Be Filled By O.E.M. To Be Filled By O.E.M./E350M1
EIP: 0060:[<c1aa13ce>] EFLAGS: 00010012 CPU: 0
EIP is at memmap_init_zone+0x6c/0xf2
EAX: 00000000 EBX: 000a8000 ECX: 000a7fff EDX: f2c00b80
ESI: 000a8000 EDI: f2c00800 EBP: c19ffe54 ESP: c19ffe34
DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
Process swapper (pid: 0, ti=3Dc19fe000 task=3Dc1a07f60 task.ti=3Dc19fe000)
Stack:
00000002 00000000 0023f000 00000000 10000000 00000a00 f2c00000 f2c00b58
c19ffeb0 c1a80f24 000375fe 00000000 f2c00800 00000800 00000100 00000030
c1abb768 0000003c 00000000 00000000 00000004 00207a02 f2c00800 000375fe
Call Trace:
[<c1a80f24>] free_area_init_node+0x358/0x385
[<c1a81384>] free_area_init_nodes+0x420/0x487
[<c1a79326>] paging_init+0x114/0x11b
[<c1a6cb13>] setup_arch+0xb37/0xc0a
[<c1a69554>] start_kernel+0x76/0x316
[<c1a690a8>] i386_start_kernel+0xa8/0xb0
This patch fixes the bug by defining early_pfn_valid() to be the
same as pfn_valid() when DISCONTIGMEM.
Reported-bisected-and-tested-by: Conny Seidel <conny.seidel@amd.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: hans.rosenfeld@amd.com
Cc: Christoph Lameter <cl@linux.com>
Cc: Conny Seidel <conny.seidel@amd.com>
Link: http://lkml.kernel.org/r/20110628094107.GB3386@htj.dyndns.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In the past we would use the GSI value to preset the ACPI SCI
IRQ which worked great as GSI == IRQ:
ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level)
While that is most often seen, there are some oddities:
ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 20 low level)
which means that GSI 20 (or pin 20) is to be overriden for IRQ 9.
Our code that presets the interrupt for ACPI SCI however would
use the GSI 20 instead of IRQ 9 ending up with:
xen: sci override: global_irq=20 trigger=0 polarity=1
xen: registering gsi 20 triggering 0 polarity 1
xen: --> pirq=20 -> irq=20
xen: acpi sci 20
.. snip..
calling acpi_init+0x0/0xbc @ 1
ACPI: SCI (IRQ9) allocation failed
ACPI Exception: AE_NOT_ACQUIRED, Unable to install System Control Interrupt handler (20110413/evevent-119)
ACPI: Unable to start the ACPI Interpreter
as the ACPI interpreter made a call to 'acpi_gsi_to_irq' which got nine.
It used that value to request an IRQ (request_irq) and since that was not
present it failed.
The fix is to recognize that for interrupts that are overriden (in our
case we only care about the ACPI SCI) we should use the IRQ number
to present the IRQ instead of the using GSI. End result is that we get:
xen: sci override: global_irq=20 trigger=0 polarity=1
xen: registering gsi 20 triggering 0 polarity 1
xen: --> pirq=20 -> irq=9 (gsi=9)
xen: acpi sci 9
which fixes the ACPI interpreter failing on startup.
CC: stable@kernel.org
Reported-by: Liwei <xieliwei@gmail.com>
Tested-by: Liwei <xieliwei@gmail.com>
[http://lists.xensource.com/archives/html/xen-devel/2011-06/msg01727.html]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Simple enough - we use an extern defined symbol which is not
defined when CONFIG_SMP is not defined. This fixes the linker
dying.
CC: stable@kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
%rip-relative addressing is relative to the first byte of the next instruction,
so we need to add %rip only after we've fetched any immediate bytes.
Based on original patch by Li Xin <xin.li@intel.com>.
Signed-off-by: Avi Kivity <avi@redhat.com>
Acked-by: Li Xin <xin.li@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Trying to build the Intel SCU Watchdog fails for me with gcc 4.6.0 -
$ gcc --version | head -n 1
gcc (GCC) 4.6.0 20110513 (prerelease)
like this :
CC drivers/watchdog/intel_scu_watchdog.o
In file included from drivers/watchdog/intel_scu_watchdog.c:49:0:
/home/jj/src/linux-2.6/arch/x86/include/asm/apb_timer.h: In function ‘apbt_time_init’:
/home/jj/src/linux-2.6/arch/x86/include/asm/apb_timer.h:65:42: warning: ‘return’ with a value, in function returning void [enabled by default]
drivers/watchdog/intel_scu_watchdog.c: In function ‘intel_scu_watchdog_init’:
drivers/watchdog/intel_scu_watchdog.c:468:2: error: implicit declaration of function ‘sfi_get_mtmr’ [-Werror=implicit-function-declaration]
drivers/watchdog/intel_scu_watchdog.c:468:32: warning: assignment makes pointer from integer without a cast [enabled by default]
cc1: some warnings being treated as errors
make[1]: *** [drivers/watchdog/intel_scu_watchdog.o] Error 1
make: *** [drivers/watchdog/intel_scu_watchdog.o] Error 2
Additionally, linux/types.h is needlessly being included twice in
drivers/watchdog/intel_scu_watchdog.c
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
commit 21a3c96 uses node_start/end_pfn(nid) for detection start/end
of nodes. But, it's not defined in linux/mmzone.h but defined in
/arch/???/include/mmzone.h which is included only under
CONFIG_NEED_MULTIPLE_NODES=y.
Then, we see
mm/page_cgroup.c: In function 'page_cgroup_init':
mm/page_cgroup.c:308: error: implicit declaration of function 'node_start_pfn'
mm/page_cgroup.c:309: error: implicit declaration of function 'node_end_pfn'
So, fixiing page_cgroup.c is an idea...
But node_start_pfn()/node_end_pfn() is a very generic macro and
should be implemented in the same manner for all archs.
(m32r has different implementation...)
This patch removes definitions of node_start/end_pfn() in each archs
and defines a unified one in linux/mmzone.h. It's not under
CONFIG_NEED_MULTIPLE_NODES, now.
A result of macro expansion is here (mm/page_cgroup.c)
for !NUMA
start_pfn = ((&contig_page_data)->node_start_pfn);
end_pfn = ({ pg_data_t *__pgdat = (&contig_page_data); __pgdat->node_start_pfn + __pgdat->node_spanned_pages;});
for NUMA (x86-64)
start_pfn = ((node_data[nid])->node_start_pfn);
end_pfn = ({ pg_data_t *__pgdat = (node_data[nid]); __pgdat->node_start_pfn + __pgdat->node_spanned_pages;});
Changelog:
- fixed to avoid using "nid" twice in node_end_pfn() macro.
Reported-and-acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Reported-and-tested-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
x86/PCI/ACPI: fix type mismatch
PCI: fix new kernel-doc warning
PCI: Fix warning in drivers/pci/probe.c on sparc64
* 'stable/bug.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/setup: Fix for incorrect xen_extra_mem_start.
xen: When calling power_off, don't call the halt function.
xen: Fix compile warning when CONFIG_SMP is not defined.
xen: support CONFIG_MAXSMP
xen: partially revert "xen: set max_pfn_mapped to the last pfn mapped"
* 'kvm-updates/3.0' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: Fix register corruption in pvclock_scale_delta
KVM: MMU: fix opposite condition in mapping_level_dirty_bitmap
KVM: VMX: do not overwrite uptodate vcpu->arch.cr3 on KVM_SET_SREGS
KVM: MMU: Fix build warnings in walk_addr_generic()
The 128-bit multiply in pvclock.h was missing an output constraint for
EDX which caused a register corruption to appear. Thanks to Ulrich for
diagnosing the EDX corruption and Avi for providing this fix.
Signed-off-by: Zachary Amsden <zamsden@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The condition is opposite, it always maps huge page for the dirty tracked page
Reported-by: Steve <stefan.bosak@gmail.com>
Signed-off-by: Steve <stefan.bosak@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Only decache guest CR3 value if vcpu->arch.cr3 is stale.
Fixes loadvm with live guest.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Tested-by: Markus Schade <markus.schade@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
On 3.0-rc1 I get
In file included from arch/x86/kvm/mmu.c:2856:
arch/x86/kvm/paging_tmpl.h: In function ‘paging32_walk_addr_generic’:
arch/x86/kvm/paging_tmpl.h:124: warning: ‘ptep_user’ may be used uninitialized in this function
In file included from arch/x86/kvm/mmu.c:2852:
arch/x86/kvm/paging_tmpl.h: In function ‘paging64_walk_addr_generic’:
arch/x86/kvm/paging_tmpl.h:124: warning: ‘ptep_user’ may be used uninitialized in this function
caused by 6e2ca7d180. According to Takuya
Yoshikawa, ptep_user won't be used uninitialized so shut up gcc.
Cc: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Link: http://lkml.kernel.org/r/20110530094604.GC21833@liondog.tnic
Signed-off-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Commit 916f676f8d started reserving boot service code since some systems
require you to keep that code around until SetVirtualAddressMap is called.
However, in some cases those areas will overlap with reserved regions.
The proper medium-term fix is to fix the bootloader to prevent the
conflicts from occurring by moving the kernel to a better position,
but the kernel should check for this possibility, and only reserve regions
which can be reserved.
Signed-off-by: Maarten Lankhorst <m.b.lankhorst@gmail.com>
Link: http://lkml.kernel.org/r/4DF7A005.1050407@gmail.com
Acked-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The earlier attempts (24bdb0b62c)
at fixing this problem caused other problems to surface (PV guests
with no PCI passthrough would have SWIOTLB turned on - which meant
64MB of precious contingous DMA32 memory being eaten up per guest).
The problem was: "on xen we add an extra memory region at the end of
the e820, and on this particular machine this extra memory region
would start below 4g and cross over the 4g boundary:
[0xfee01000-0x192655000)
Unfortunately e820_end_of_low_ram_pfn does not expect an
e820 layout like that so it returns 4g, therefore initial_memory_mapping
will map [0 - 0x100000000), that is a memory range that includes some
reserved memory regions."
The memory range was the IOAPIC regions, and with the 1-1 mapping
turned on, it would map them as RAM, not as MMIO regions. This caused
the hypervisor to complain. Fortunately this is experienced only under
the initial domain so we guard for it.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
.. As it won't actually power off the machine.
Reported-by: Sven Köhler <sven.koehler@gmail.com>
Tested-by: Sven Köhler <sven.koehler@gmail.com>
Signed-off-by: Tom Goetz <tom.goetz@virtualcomputer.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>