linux/arch/x86
Juergen Gross eafd72e016 xen: avoid early crash of memory limited dom0
Commit b1c9f169047b ("xen: split counting of extra memory pages...")
introduced an error when dom0 was started with limited memory.

The problem arises in case dom0 is started with initial memory and
maximum memory being the same and exactly a multiple of 1 GB. The
kernel must be configured without CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
for the problem to happen. In this case it will crash very early
during boot due to the virtual mapped p2m list not being large
enough to be able to remap any memory:

(XEN) Freed 304kB init memory.
mapping kernel into physical memory
about to get started...
(XEN) traps.c:459:d0v0 Unhandled invalid opcode fault/trap [#6] on VCPU 0 [ec=0000]
(XEN) domain_crash_sync called from entry.S: fault at ffff82d080229a93 create_bounce_frame+0x12b/0x13a
(XEN) Domain 0 (vcpu#0) crashed on cpu#0:
(XEN) ----[ Xen-4.5.2-pre  x86_64  debug=n Not tainted ]----
(XEN) CPU:    0
(XEN) RIP:    e033:[<ffffffff81d120cb>]
(XEN) RFLAGS: 0000000000000206   EM: 1 CONTEXT: pv guest (d0v0)
(XEN) rax: ffffffff81db2000   rbx: 000000004d000000   rcx: 0000000000000000
(XEN) rdx: 000000004d000000   rsi: 0000000000063000   rdi: 000000004d063000
(XEN) rbp: ffffffff81c03d78   rsp: ffffffff81c03d28   r8:  0000000000023000
(XEN) r9:  00000001040ff000   r10: 0000000000007ff0   r11: 0000000000000000
(XEN) r12: 0000000000063000   r13: 000000000004d000   r14: 0000000000000063
(XEN) r15: 0000000000000063   cr0: 0000000080050033   cr4: 00000000000006f0
(XEN) cr3: 0000000105c0f000   cr2: ffffc90000268000
(XEN) ds: 0000   es: 0000   fs: 0000   gs: 0000   ss: e02b   cs: e033
(XEN) Guest stack trace from rsp=ffffffff81c03d28:
(XEN)   0000000000000000 0000000000000000 ffffffff81d120cb 000000010000e030
(XEN)   0000000000010006 ffffffff81c03d68 000000000000e02b ffffffffffffffff
(XEN)   0000000000000063 000000000004d063 ffffffff81c03de8 ffffffff81d130a7
(XEN)   ffffffff81c03de8 000000000004d000 00000001040ff000 0000000000105db1
(XEN)   00000001040ff001 000000000004d062 ffff8800092d6ff8 0000000002027000
(XEN)   ffff8800094d8340 ffff8800092d6ff8 00003ffffffff000 ffff8800092d7ff8
(XEN)   ffffffff81c03e48 ffffffff81d13c43 ffff8800094d8000 ffff8800094d9000
(XEN)   0000000000000000 ffff8800092d6000 00000000092d6000 000000004cfbf000
(XEN)   00000000092d6000 00000000052d5442 0000000000000000 0000000000000000
(XEN)   ffffffff81c03ed8 ffffffff81d185c1 0000000000000000 0000000000000000
(XEN)   ffffffff81c03e78 ffffffff810f8ca4 ffffffff81c03ed8 ffffffff8171a15d
(XEN)   0000000000000010 ffffffff81c03ee8 0000000000000000 0000000000000000
(XEN)   ffffffff81f0e402 ffffffffffffffff ffffffff81dae900 0000000000000000
(XEN)   0000000000000000 0000000000000000 ffffffff81c03f28 ffffffff81d0cf0f
(XEN)   0000000000000000 0000000000000000 0000000000000000 ffffffff81db82e0
(XEN)   0000000000000000 0000000000000000 0000000000000000 0000000000000000
(XEN)   ffffffff81c03f38 ffffffff81d0c603 ffffffff81c03ff8 ffffffff81d11c86
(XEN)   0300000100000032 0000000000000005 0000000000000020 0000000000000000
(XEN)   0000000000000000 0000000000000000 0000000000000000 0000000000000000
(XEN)   0000000000000000 0000000000000000 0000000000000000 0000000000000000
(XEN) Domain 0 crashed: rebooting machine in 5 seconds.

This can be avoided by allocating aneough space for the p2m to cover
the maximum memory of dom0 plus the identity mapped holes required
for PCI space, BIOS etc.

Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08 16:28:04 +01:00
..
boot x86/efi: Use all 64 bit of efi_memmap in setup_e820() 2015-07-30 18:07:10 +01:00
configs kconfig: add xenconfig defconfig helper 2015-06-16 11:04:29 +01:00
crypto crypto: aesni - fix failing setkey for rfc4106-gcm-aesni 2015-06-29 16:06:30 +08:00
entry x86: fix error handling for 32-bit compat out-of-range system call numbers 2015-08-13 16:19:44 -07:00
ia32 Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-06-22 17:59:09 -07:00
include xen/PMU: Initialization code for Xen PMU 2015-08-20 12:25:20 +01:00
kernel Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-08-16 15:11:25 -07:00
kvm KVM: x86: Use adjustment in guest cycles when handling MSR_IA32_TSC_ADJUST 2015-08-07 13:28:03 +02:00
lguest Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-06-22 17:59:09 -07:00
lib perf/x86: Fix copy_from_user_nmi() return if range is not ok 2015-07-06 14:09:27 +02:00
math-emu x86/ldt: Further fix FPU emulation 2015-08-16 15:11:05 -07:00
mm x86/mm/pat: Revert 'Adjust default caching mode translation tables' 2015-07-26 10:27:37 +02:00
net ebpf, x86: fix general protection fault when tail call is invoked 2015-07-29 17:02:19 -07:00
oprofile x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
pci PCI changes for the v4.2 merge window: 2015-06-23 13:41:24 -07:00
platform efi: Check for NULL efi kernel parameters 2015-07-30 18:07:11 +01:00
power x86/ldt: Make modify_ldt synchronous 2015-07-31 10:23:23 +02:00
purgatory Merge branches 'x86-build-for-linus', 'x86-cleanups-for-linus' and 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-12-10 12:35:46 -08:00
realmode Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-02-16 14:58:12 -08:00
tools x86, build: replace Perl script with Shell script 2015-01-26 13:37:18 -08:00
um Merge branch 'for-linus-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2015-06-28 13:55:08 -07:00
video
xen xen: avoid early crash of memory limited dom0 2015-09-08 16:28:04 +01:00
.gitignore
Kbuild x86/asm/entry, x86/vdso: Move the vDSO code to arch/x86/entry/vdso/ 2015-06-03 18:51:37 +02:00
Kconfig x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86 2015-07-18 03:42:51 +02:00
Kconfig.cpu
Kconfig.debug x86/entry/64, x86/nmi/64: Add CONFIG_DEBUG_ENTRY NMI testing code 2015-07-17 12:50:14 +02:00
Makefile x86/asm/entry: Move the arch/x86/syscalls/ definitions to arch/x86/entry/syscalls/ 2015-06-04 07:37:37 +02:00
Makefile_32.cpu
Makefile.um kbuild: use relative path more to include Makefile 2015-04-02 16:42:08 +02:00