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* x86: Fix typo in kexec register clearingKees Cook2013-06-201-1/+1
| | | | | | | | | | | | | | commit c8a22d19dd238ede87aa0ac4f7dbea8da039b9c1 upstream. Fixes a typo in register clearing code. Thanks to PaX Team for fixing this originally, and James Troup for pointing it out. Signed-off-by: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/20130605184718.GA8396@www.outflux.net Cc: PaX Team <pageexec@freemail.hu> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* um: Serve io_remap_pfn_range()Richard Weinberger2013-06-071-0/+2
| | | | | | | | | | | | commit 4d94d6d030adfdea4837694d293ec6918d133ab2 upstream. At some places io_remap_pfn_range() is needed. UML has to serve it like all other archs do. Signed-off-by: Richard Weinberger <richard@nod.at> Tested-by: Antoine Martin <antoine@nagafix.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Kirkwood: Enable PCIe port 1 on QNAP TS-11x/TS-21xMartin Michlmayr2013-06-071-1/+1
| | | | | | | | | | | | | | | commit 99e11334dcb846f9b76fb808196c7f47aa83abb3 upstream. Enable KW_PCIE1 on QNAP TS-11x/TS-21x devices as newer revisions (rev 1.3) have a USB 3.0 chip from Etron on PCIe port 1. Thanks to Marek Vasut for identifying this issue! Signed-off-by: Martin Michlmayr <tbm@cyrius.com> Tested-by: Marek Vasut <marex@denx.de> Acked-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: plat-orion: Fix num_resources and id for ge10 and ge11Gregory CLEMENT2013-06-071-6/+6
| | | | | | | | | | | | | | | | commit 2b8b2797142c7951e635c6eec5d1705ee9bc45c5 upstream. When platform data were moved from arch/arm/mach-mv78xx0/common.c to arch/arm/plat-orion/common.c with the commit "7e3819d ARM: orion: Consolidate ethernet platform data", there were few typo made on gigabit Ethernet interface ge10 and ge11. This commit writes back their initial value, which allows to use this interfaces again. Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Acked-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* avr32: fix relocation check for signed 18-bit offsetHans-Christian Egtvedt2013-06-071-1/+1
| | | | | | | | | | | commit e68c636d88db3fda74e664ecb1a213ae0d50a7d8 upstream. Caught by static code analysis by David. Reported-by: David Binderman <dcb314@hotmail.com> Signed-off-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.Konrad Rzeszutek Wilk2013-05-191-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7f1fc268c47491fd5e63548f6415fc8604e13003 upstream. If a user did: echo 0 > /sys/devices/system/cpu/cpu1/online echo 1 > /sys/devices/system/cpu/cpu1/online we would (this a build with DEBUG enabled) get to: smpboot: ++++++++++++++++++++=_---CPU UP 1 .. snip.. smpboot: Stack at about ffff880074c0ff44 smpboot: CPU1: has booted. and hang. The RCU mechanism would kick in an try to IPI the CPU1 but the IPIs (and all other interrupts) would never arrive at the CPU1. At first glance at least. A bit digging in the hypervisor trace shows that (using xenanalyze): [vla] d4v1 vec 243 injecting 0.043163027 --|x d4v1 intr_window vec 243 src 5(vector) intr f3 ] 0.043163639 --|x d4v1 vmentry cycles 1468 ] 0.043164913 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254 0.043164913 --|x d4v1 inj_virq vec 243 real [vla] d4v1 vec 243 injecting 0.043164913 --|x d4v1 intr_window vec 243 src 5(vector) intr f3 ] 0.043165526 --|x d4v1 vmentry cycles 1472 ] 0.043166800 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254 0.043166800 --|x d4v1 inj_virq vec 243 real [vla] d4v1 vec 243 injecting there is a pending event (subsequent debugging shows it is the IPI from the VCPU0 when smpboot.c on VCPU1 has done "set_cpu_online(smp_processor_id(), true)") and the guest VCPU1 is interrupted with the callback IPI (0xf3 aka 243) which ends up calling __xen_evtchn_do_upcall. The __xen_evtchn_do_upcall seems to do *something* but not acknowledge the pending events. And the moment the guest does a 'cli' (that is the ffffffff81673254 in the log above) the hypervisor is invoked again to inject the IPI (0xf3) to tell the guest it has pending interrupts. This repeats itself forever. The culprit was the per_cpu(xen_vcpu, cpu) pointer. At the bootup we set each per_cpu(xen_vcpu, cpu) to point to the shared_info->vcpu_info[vcpu] but later on use the VCPUOP_register_vcpu_info to register per-CPU structures (xen_vcpu_setup). This is used to allow events for more than 32 VCPUs and for performance optimizations reasons. When the user performs the VCPU hotplug we end up calling the the xen_vcpu_setup once more. We make the hypercall which returns -EINVAL as it does not allow multiple registration calls (and already has re-assigned where the events are being set). We pick the fallback case and set per_cpu(xen_vcpu, cpu) to point to the shared_info->vcpu_info[vcpu] (which is a good fallback during bootup). However the hypervisor is still setting events in the register per-cpu structure (per_cpu(xen_vcpu_info, cpu)). As such when the events are set by the hypervisor (such as timer one), and when we iterate in __xen_evtchn_do_upcall we end up reading stale events from the shared_info->vcpu_info[vcpu] instead of the per_cpu(xen_vcpu_info, cpu) structures. Hence we never acknowledge the events that the hypervisor has set and the hypervisor keeps on reminding us to ack the events which we never do. The fix is simple. Don't on the second time when xen_vcpu_setup is called over-write the per_cpu(xen_vcpu, cpu) if it points to per_cpu(xen_vcpu_info). Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: OMAP: RX-51: change probe order of touchscreen and panel SPI devicesAaro Koskinen2013-05-191-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e65f131a14726e5f1b880a528271a52428e5b3a5 upstream. Commit 9fdca9df (spi: omap2-mcspi: convert to module_platform_driver) broke the SPI display/panel driver probe on RX-51/N900. The exact cause is not fully understood, but it seems to be related to the probe order. SPI communication to the panel driver (spi1.2) fails unless the touchscreen (spi1.0) has been probed/initialized before. When the omap2-mcspi driver was converted to a platform driver, it resulted in that the devices are probed immediately after the board registers them in the order they are listed in the board file. Fix the issue by moving the touchscreen before the panel in the SPI device list. The patch fixes the following failure: [ 1.260955] acx565akm spi1.2: invalid display ID [ 1.265899] panel-acx565akm display0: acx_panel_probe panel detect error [ 1.273071] omapdss CORE error: driver probe failed: -19 Tested-by: Sebastian Reichel <sre@debian.org> Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Cc: Pali Rohár <pali.rohar@gmail.com> Cc: Joni Lapilainen <joni.lapilainen@gmail.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: VMX: fix halt emulation while emulating invalid guest sateGleb Natapov2013-05-191-0/+6
| | | | | | | | | | | | | | | | | | commit 8d76c49e9ffeee839bc0b7a3278a23f99101263e upstream. The invalid guest state emulation loop does not check halt_request which causes 100% cpu loop while guest is in halt and in invalid state, but more serious issue is that this leaves halt_request set, so random instruction emulated by vm86 #GP exit can be interpreted as halt which causes guest hang. Fix both problems by handling halt_request in emulation loop. Reported-by: Tomas Papan <tomas.papan@gmail.com> Tested-by: Tomas Papan <tomas.papan@gmail.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Revert "x86, amd: Disable way access filter on Piledriver CPUs" it is duplicatedAndre Przywara2013-05-111-14/+0
| | | | | | | | | | | | | | | | Revert 5e3fe67e02c53e5a5fcf0e2b0d91dd93f757d50b which is commit 2bbf0a1427c377350f001fbc6260995334739ad7 upstream. Willy pointed out that I messed up and applied this one twice to the 3.0-stable tree, so revert the second instance of it. Reported by: Willy Tarreau <w@1wt.eu> Cc: Andre Przywara <osp@andrep.de> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: CAI Qian <caiqian@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> reverted:
* x86/mm: account for PGDIR_SIZE alignmentJerry Hoemann2013-05-111-0/+5
| | | | | | | | | | | | | | | | | | | | | | Patch for -stable. Function find_early_table_space removed upstream. Fixes panic in alloc_low_page due to pgt_buf overflow during init_memory_mapping. find_early_table_space sizes pgt_buf based upon the size of the memory being mapped, but it does not take into account the alignment of the memory. When the region being mapped spans a 512GB (PGDIR_SIZE) alignment, a panic from alloc_low_pages occurs. kernel_physical_mapping_init takes into account PGDIR_SIZE alignment. This causes an extra call to alloc_low_page to be made. This extra call isn't accounted for by find_early_table_space and causes a kernel panic. Change is to take into account PGDIR_SIZE alignment in find_early_table_space. Signed-off-by: Jerry Hoemann <jerry.hoemann@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: fix numa distance for form0 device treeVaidyanathan Srinivasan2013-05-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7122beeee7bc1757682049780179d7c216dd1c83 upstream. The following commit breaks numa distance setup for old powerpc systems that use form0 encoding in device tree. commit 41eab6f88f24124df89e38067b3766b7bef06ddb powerpc/numa: Use form 1 affinity to setup node distance Device tree node /rtas/ibm,associativity-reference-points would index into /cpus/PowerPCxxxx/ibm,associativity based on form0 or form1 encoding detected by ibm,architecture-vec-5 property. All modern systems use form1 and current kernel code is correct. However, on older systems with form0 encoding, the numa distance will get hard coded as LOCAL_DISTANCE for all nodes. This causes task scheduling anomaly since scheduler will skip building numa level domain (topmost domain with all cpus) if all numa distances are same. (value of 'level' in sched_init_numa() will remain 0) Prior to the above commit: ((from) == (to) ? LOCAL_DISTANCE : REMOTE_DISTANCE) Restoring compatible behavior with this patch for old powerpc systems with device tree where numa distance are encoded as form0. Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* s390: move dummy io_remap_pfn_range() to asm/pgtable.hLinus Torvalds2013-05-071-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | commit 4f2e29031e6c67802e7370292dd050fd62f337ee upstream. Commit b4cbb197c7e7 ("vm: add vm_iomap_memory() helper function") added a helper function wrapper around io_remap_pfn_range(), and every other architecture defined it in <asm/pgtable.h>. The s390 choice of <asm/io.h> may make sense, but is not very convenient for this case, and gratuitous differences like that cause unexpected errors like this: mm/memory.c: In function 'vm_iomap_memory': mm/memory.c:2439:2: error: implicit declaration of function 'io_remap_pfn_range' [-Werror=implicit-function-declaration] Glory be the kbuild test robot who noticed this, bisected it, and reported it to the guilty parties (ie me). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86: Eliminate irq_mis_count counted in arch_irq_statLi Fei2013-05-071-4/+0
| | | | | | | | | | | | | | | | | | | | | commit f7b0e1055574ce06ab53391263b4e205bf38daf3 upstream. With the current implementation, kstat_cpu(cpu).irqs_sum is also increased in case of irq_mis_count increment. So there is no need to count irq_mis_count in arch_irq_stat, otherwise irq_mis_count will be counted twice in the sum of /proc/stat. Reported-by: Liu Chuansheng <chuansheng.liu@intel.com> Signed-off-by: Li Fei <fei.li@intel.com> Acked-by: Liu Chuansheng <chuansheng.liu@intel.com> Cc: tomoki.sekiyama.qu@hitachi.com Cc: joe@perches.com Link: http://lkml.kernel.org/r/1366980611.32469.7.camel@fli24-HP-Compaq-8100-Elite-CMT-PC Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Wrong asm register contraints in the kvm implementationStephan Schreiber2013-05-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit de53e9caa4c6149ef4a78c2f83d7f5b655848767 upstream. The Linux Kernel contains some inline assembly source code which has wrong asm register constraints in arch/ia64/kvm/vtlb.c. I observed this on Kernel 3.2.35 but it is also true on the most recent Kernel 3.9-rc1. File arch/ia64/kvm/vtlb.c: u64 guest_vhpt_lookup(u64 iha, u64 *pte) { u64 ret; struct thash_data *data; data = __vtr_lookup(current_vcpu, iha, D_TLB); if (data != NULL) thash_vhpt_insert(current_vcpu, data->page_flags, data->itir, iha, D_TLB); asm volatile ( "rsm psr.ic|psr.i;;" "srlz.d;;" "ld8.s r9=[%1];;" "tnat.nz p6,p7=r9;;" "(p6) mov %0=1;" "(p6) mov r9=r0;" "(p7) extr.u r9=r9,0,53;;" "(p7) mov %0=r0;" "(p7) st8 [%2]=r9;;" "ssm psr.ic;;" "srlz.d;;" "ssm psr.i;;" "srlz.d;;" : "=r"(ret) : "r"(iha), "r"(pte):"memory"); return ret; } The list of output registers is : "=r"(ret) : "r"(iha), "r"(pte):"memory"); The constraint "=r" means that the GCC has to maintain that these vars are in registers and contain valid info when the program flow leaves the assembly block (output registers). But "=r" also means that GCC can put them in registers that are used as input registers. Input registers are iha, pte on the example. If the predicate p7 is true, the 8th assembly instruction "(p7) mov %0=r0;" is the first one which writes to a register which is maintained by the register constraints; it sets %0. %0 means the first register operand; it is ret here. This instruction might overwrite the %2 register (pte) which is needed by the next instruction: "(p7) st8 [%2]=r9;;" Whether it really happens depends on how GCC decides what registers it uses and how it optimizes the code. The attached patch fixes the register operand constraints in arch/ia64/kvm/vtlb.c. The register constraints should be : "=&r"(ret) : "r"(iha), "r"(pte):"memory"); The & means that GCC must not use any of the input registers to place this output register in. This is Debian bug#702639 (http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=702639). The patch is applicable on Kernel 3.9-rc1, 3.2.35 and many other versions. Signed-off-by: Stephan Schreiber <info@fs-driver.org> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Wrong asm register contraints in the futex implementationStephan Schreiber2013-05-071-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 136f39ddc53db3bcee2befbe323a56d4fbf06da8 upstream. The Linux Kernel contains some inline assembly source code which has wrong asm register constraints in arch/ia64/include/asm/futex.h. I observed this on Kernel 3.2.23 but it is also true on the most recent Kernel 3.9-rc1. File arch/ia64/include/asm/futex.h: static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval, u32 newval) { if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) return -EFAULT; { register unsigned long r8 __asm ("r8"); unsigned long prev; __asm__ __volatile__( " mf;; \n" " mov %0=r0 \n" " mov ar.ccv=%4;; \n" "[1:] cmpxchg4.acq %1=[%2],%3,ar.ccv \n" " .xdata4 \"__ex_table\", 1b-., 2f-. \n" "[2:]" : "=r" (r8), "=r" (prev) : "r" (uaddr), "r" (newval), "rO" ((long) (unsigned) oldval) : "memory"); *uval = prev; return r8; } } The list of output registers is : "=r" (r8), "=r" (prev) The constraint "=r" means that the GCC has to maintain that these vars are in registers and contain valid info when the program flow leaves the assembly block (output registers). But "=r" also means that GCC can put them in registers that are used as input registers. Input registers are uaddr, newval, oldval on the example. The second assembly instruction " mov %0=r0 \n" is the first one which writes to a register; it sets %0 to 0. %0 means the first register operand; it is r8 here. (The r0 is read-only and always 0 on the Itanium; it can be used if an immediate zero value is needed.) This instruction might overwrite one of the other registers which are still needed. Whether it really happens depends on how GCC decides what registers it uses and how it optimizes the code. The objdump utility can give us disassembly. The futex_atomic_cmpxchg_inatomic() function is inline, so we have to look for a module that uses the funtion. This is the cmpxchg_futex_value_locked() function in kernel/futex.c: static int cmpxchg_futex_value_locked(u32 *curval, u32 __user *uaddr, u32 uval, u32 newval) { int ret; pagefault_disable(); ret = futex_atomic_cmpxchg_inatomic(curval, uaddr, uval, newval); pagefault_enable(); return ret; } Now the disassembly. At first from the Kernel package 3.2.23 which has been compiled with GCC 4.4, remeber this Kernel seemed to work: objdump -d linux-3.2.23/debian/build/build_ia64_none_mckinley/kernel/futex.o 0000000000000230 <cmpxchg_futex_value_locked>: 230: 0b 18 80 1b 18 21 [MMI] adds r3=3168,r13;; 236: 80 40 0d 00 42 00 adds r8=40,r3 23c: 00 00 04 00 nop.i 0x0;; 240: 0b 50 00 10 10 10 [MMI] ld4 r10=[r8];; 246: 90 08 28 00 42 00 adds r9=1,r10 24c: 00 00 04 00 nop.i 0x0;; 250: 09 00 00 00 01 00 [MMI] nop.m 0x0 256: 00 48 20 20 23 00 st4 [r8]=r9 25c: 00 00 04 00 nop.i 0x0;; 260: 08 10 80 06 00 21 [MMI] adds r2=32,r3 266: 00 00 00 02 00 00 nop.m 0x0 26c: 02 08 f1 52 extr.u r16=r33,0,61 270: 05 40 88 00 08 e0 [MLX] addp4 r8=r34,r0 276: ff ff 0f 00 00 e0 movl r15=0xfffffffbfff;; 27c: f1 f7 ff 65 280: 09 70 00 04 18 10 [MMI] ld8 r14=[r2] 286: 00 00 00 02 00 c0 nop.m 0x0 28c: f0 80 1c d0 cmp.ltu p6,p7=r15,r16;; 290: 08 40 fc 1d 09 3b [MMI] cmp.eq p8,p9=-1,r14 296: 00 00 00 02 00 40 nop.m 0x0 29c: e1 08 2d d0 cmp.ltu p10,p11=r14,r33 2a0: 56 01 10 00 40 10 [BBB] (p10) br.cond.spnt.few 2e0 <cmpxchg_futex_value_locked+0xb0> 2a6: 02 08 00 80 21 03 (p08) br.cond.dpnt.few 2b0 <cmpxchg_futex_value_locked+0x80> 2ac: 40 00 00 41 (p06) br.cond.spnt.few 2e0 <cmpxchg_futex_value_locked+0xb0> 2b0: 0a 00 00 00 22 00 [MMI] mf;; 2b6: 80 00 00 00 42 00 mov r8=r0 2bc: 00 00 04 00 nop.i 0x0 2c0: 0b 00 20 40 2a 04 [MMI] mov.m ar.ccv=r8;; 2c6: 10 1a 85 22 20 00 cmpxchg4.acq r33=[r33],r35,ar.ccv 2cc: 00 00 04 00 nop.i 0x0;; 2d0: 10 00 84 40 90 11 [MIB] st4 [r32]=r33 2d6: 00 00 00 02 00 00 nop.i 0x0 2dc: 20 00 00 40 br.few 2f0 <cmpxchg_futex_value_locked+0xc0> 2e0: 09 40 c8 f9 ff 27 [MMI] mov r8=-14 2e6: 00 00 00 02 00 00 nop.m 0x0 2ec: 00 00 04 00 nop.i 0x0;; 2f0: 0b 58 20 1a 19 21 [MMI] adds r11=3208,r13;; 2f6: 20 01 2c 20 20 00 ld4 r18=[r11] 2fc: 00 00 04 00 nop.i 0x0;; 300: 0b 88 fc 25 3f 23 [MMI] adds r17=-1,r18;; 306: 00 88 2c 20 23 00 st4 [r11]=r17 30c: 00 00 04 00 nop.i 0x0;; 310: 11 00 00 00 01 00 [MIB] nop.m 0x0 316: 00 00 00 02 00 80 nop.i 0x0 31c: 08 00 84 00 br.ret.sptk.many b0;; The lines 2b0: 0a 00 00 00 22 00 [MMI] mf;; 2b6: 80 00 00 00 42 00 mov r8=r0 2bc: 00 00 04 00 nop.i 0x0 2c0: 0b 00 20 40 2a 04 [MMI] mov.m ar.ccv=r8;; 2c6: 10 1a 85 22 20 00 cmpxchg4.acq r33=[r33],r35,ar.ccv 2cc: 00 00 04 00 nop.i 0x0;; are the instructions of the assembly block. The line 2b6: 80 00 00 00 42 00 mov r8=r0 sets the r8 register to 0 and after that 2c0: 0b 00 20 40 2a 04 [MMI] mov.m ar.ccv=r8;; prepares the 'oldvalue' for the cmpxchg but it takes it from r8. This is wrong. What happened here is what I explained above: An input register is overwritten which is still needed. The register operand constraints in futex.h are wrong. (The problem doesn't occur when the Kernel is compiled with GCC 4.6.) The attached patch fixes the register operand constraints in futex.h. The code after patching of it: static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval, u32 newval) { if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) return -EFAULT; { register unsigned long r8 __asm ("r8") = 0; unsigned long prev; __asm__ __volatile__( " mf;; \n" " mov ar.ccv=%4;; \n" "[1:] cmpxchg4.acq %1=[%2],%3,ar.ccv \n" " .xdata4 \"__ex_table\", 1b-., 2f-. \n" "[2:]" : "+r" (r8), "=&r" (prev) : "r" (uaddr), "r" (newval), "rO" ((long) (unsigned) oldval) : "memory"); *uval = prev; return r8; } } I also initialized the 'r8' var with the C programming language. The _asm qualifier on the definition of the 'r8' var forces GCC to use the r8 processor register for it. I don't believe that we should use inline assembly for zeroing out a local variable. The constraint is "+r" (r8) what means that it is both an input register and an output register. Note that the page fault handler will modify the r8 register which will be the return value of the function. The real fix is "=&r" (prev) The & means that GCC must not use any of the input registers to place this output register in. Patched the Kernel 3.2.23 and compiled it with GCC4.4: 0000000000000230 <cmpxchg_futex_value_locked>: 230: 0b 18 80 1b 18 21 [MMI] adds r3=3168,r13;; 236: 80 40 0d 00 42 00 adds r8=40,r3 23c: 00 00 04 00 nop.i 0x0;; 240: 0b 50 00 10 10 10 [MMI] ld4 r10=[r8];; 246: 90 08 28 00 42 00 adds r9=1,r10 24c: 00 00 04 00 nop.i 0x0;; 250: 09 00 00 00 01 00 [MMI] nop.m 0x0 256: 00 48 20 20 23 00 st4 [r8]=r9 25c: 00 00 04 00 nop.i 0x0;; 260: 08 10 80 06 00 21 [MMI] adds r2=32,r3 266: 20 12 01 10 40 00 addp4 r34=r34,r0 26c: 02 08 f1 52 extr.u r16=r33,0,61 270: 05 40 00 00 00 e1 [MLX] mov r8=r0 276: ff ff 0f 00 00 e0 movl r15=0xfffffffbfff;; 27c: f1 f7 ff 65 280: 09 70 00 04 18 10 [MMI] ld8 r14=[r2] 286: 00 00 00 02 00 c0 nop.m 0x0 28c: f0 80 1c d0 cmp.ltu p6,p7=r15,r16;; 290: 08 40 fc 1d 09 3b [MMI] cmp.eq p8,p9=-1,r14 296: 00 00 00 02 00 40 nop.m 0x0 29c: e1 08 2d d0 cmp.ltu p10,p11=r14,r33 2a0: 56 01 10 00 40 10 [BBB] (p10) br.cond.spnt.few 2e0 <cmpxchg_futex_value_locked+0xb0> 2a6: 02 08 00 80 21 03 (p08) br.cond.dpnt.few 2b0 <cmpxchg_futex_value_locked+0x80> 2ac: 40 00 00 41 (p06) br.cond.spnt.few 2e0 <cmpxchg_futex_value_locked+0xb0> 2b0: 0b 00 00 00 22 00 [MMI] mf;; 2b6: 00 10 81 54 08 00 mov.m ar.ccv=r34 2bc: 00 00 04 00 nop.i 0x0;; 2c0: 09 58 8c 42 11 10 [MMI] cmpxchg4.acq r11=[r33],r35,ar.ccv 2c6: 00 00 00 02 00 00 nop.m 0x0 2cc: 00 00 04 00 nop.i 0x0;; 2d0: 10 00 2c 40 90 11 [MIB] st4 [r32]=r11 2d6: 00 00 00 02 00 00 nop.i 0x0 2dc: 20 00 00 40 br.few 2f0 <cmpxchg_futex_value_locked+0xc0> 2e0: 09 40 c8 f9 ff 27 [MMI] mov r8=-14 2e6: 00 00 00 02 00 00 nop.m 0x0 2ec: 00 00 04 00 nop.i 0x0;; 2f0: 0b 88 20 1a 19 21 [MMI] adds r17=3208,r13;; 2f6: 30 01 44 20 20 00 ld4 r19=[r17] 2fc: 00 00 04 00 nop.i 0x0;; 300: 0b 90 fc 27 3f 23 [MMI] adds r18=-1,r19;; 306: 00 90 44 20 23 00 st4 [r17]=r18 30c: 00 00 04 00 nop.i 0x0;; 310: 11 00 00 00 01 00 [MIB] nop.m 0x0 316: 00 00 00 02 00 80 nop.i 0x0 31c: 08 00 84 00 br.ret.sptk.many b0;; Much better. There is a 270: 05 40 00 00 00 e1 [MLX] mov r8=r0 which was generated by C code r8 = 0. Below 2b6: 00 10 81 54 08 00 mov.m ar.ccv=r34 what means that oldval is no longer overwritten. This is Debian bug#702641 (http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=702641). The patch is applicable on Kernel 3.9-rc1, 3.2.23 and many other versions. Signed-off-by: Stephan Schreiber <info@fs-driver.org> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Fix initialization of CMCI/CMCP interruptsTony Luck2013-05-073-13/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit d303e9e98fce56cdb3c6f2ac92f626fc2bd51c77 upstream. Back 2010 during a revamp of the irq code some initializations were moved from ia64_mca_init() to ia64_mca_late_init() in commit c75f2aa13f5b268aba369b5dc566088b5194377c Cannot use register_percpu_irq() from ia64_mca_init() But this was hideously wrong. First of all these initializations are now down far too late. Specifically after all the other cpus have been brought up and initialized their own CMC vectors from smp_callin(). Also ia64_mca_late_init() may be called from any cpu so the line: ia64_mca_cmc_vector_setup(); /* Setup vector on BSP */ is generally not executed on the BSP, and so the CMC vector isn't setup at all on that processor. Make use of the arch_early_irq_init() hook to get this code executed at just the right moment: not too early, not too late. Reported-by: Fred Hartnett <fred.hartnett@hp.com> Tested-by: Fred Hartnett <fred.hartnett@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* xen/time: Fix kasprintf splat when allocating timer%d IRQ line.Konrad Rzeszutek Wilk2013-05-072-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7918c92ae9638eb8a6ec18e2b4a0de84557cccc8 upstream. When we online the CPU, we get this splat: smpboot: Booting Node 0 Processor 1 APIC 0x2 installing Xen timer for CPU 1 BUG: sleeping function called from invalid context at /home/konrad/ssd/konrad/linux/mm/slab.c:3179 in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/1 Pid: 0, comm: swapper/1 Not tainted 3.9.0-rc6upstream-00001-g3884fad #1 Call Trace: [<ffffffff810c1fea>] __might_sleep+0xda/0x100 [<ffffffff81194617>] __kmalloc_track_caller+0x1e7/0x2c0 [<ffffffff81303758>] ? kasprintf+0x38/0x40 [<ffffffff813036eb>] kvasprintf+0x5b/0x90 [<ffffffff81303758>] kasprintf+0x38/0x40 [<ffffffff81044510>] xen_setup_timer+0x30/0xb0 [<ffffffff810445af>] xen_hvm_setup_cpu_clockevents+0x1f/0x30 [<ffffffff81666d0a>] start_secondary+0x19c/0x1a8 The solution to that is use kasprintf in the CPU hotplug path that 'online's the CPU. That is, do it in in xen_hvm_cpu_notify, and remove the call to in xen_hvm_setup_cpu_clockevents. Unfortunatly the later is not a good idea as the bootup path does not use xen_hvm_cpu_notify so we would end up never allocating timer%d interrupt lines when booting. As such add the check for atomic() to continue. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc/spufs: Initialise inode->i_ino in spufs_new_inode()Michael Ellerman2013-05-071-0/+1
| | | | | | | | | | | | | | | | commit 6747e83235caecd30b186d1282e4eba7679f81b7 upstream. In commit 85fe402 (fs: do not assign default i_ino in new_inode), the initialisation of i_ino was removed from new_inode() and pushed down into the callers. However spufs_new_inode() was not updated. This exhibits as no files appearing in /spu, because all our dirents have a zero inode, which readdir() seems to dislike. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: Add isync to copy_and_flushMichael Neuling2013-05-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | commit 29ce3c5073057991217916abc25628e906911757 upstream. In __after_prom_start we copy the kernel down to zero in two calls to copy_and_flush. After the first call (copy from 0 to copy_to_here:) we jump to the newly copied code soon after. Unfortunately there's no isync between the copy of this code and the jump to it. Hence it's possible that stale instructions could still be in the icache or pipeline before we branch to it. We've seen this on real machines and it's results in no console output after: calling quiesce... returning from prom_init The below adds an isync to ensure that the copy and flushing has completed before any branching to the new instructions occurs. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sparc32: support atomic64_tSam Ravnborg2013-05-012-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit aea1181b0bd0a09c54546399768f359d1e198e45 upstream, Needed to compile ext4 for sparc32 since commit 503f4bdcc078e7abee273a85ce322de81b18a224 There is no-one that really require atomic64_t support on sparc32. But several drivers fails to build without proper atomic64 support. And for an allyesconfig build for sparc32 this is annoying. Include the generic atomic64_t support for sparc32. This has a text footprint cost: $size vmlinux (before atomic64_t support) text data bss dec hex filename 3578860 134260 108781 3821901 3a514d vmlinux $size vmlinux (after atomic64_t support) text data bss dec hex filename 3579892 130684 108781 3819357 3a475d vmlinux text increase (3579892 - 3578860) = 1032 bytes data decreases - but I fail to explain why! I have rebuild twice to check my numbers. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Andreas Larsson <andreas@gaisler.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sparc64: Fix race in TLB batch processing.David S. Miller2013-05-017-55/+242
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Commits f36391d2790d04993f48da6a45810033a2cdf847 and f0af97070acbad5d6a361f485828223a4faaa0ee upstream. ] As reported by Dave Kleikamp, when we emit cross calls to do batched TLB flush processing we have a race because we do not synchronize on the sibling cpus completing the cross call. So meanwhile the TLB batch can be reset (tb->tlb_nr set to zero, etc.) and either flushes are missed or flushes will flush the wrong addresses. Fix this by using generic infrastructure to synchonize on the completion of the cross call. This first required getting the flush_tlb_pending() call out from switch_to() which operates with locks held and interrupts disabled. The problem is that smp_call_function_many() cannot be invoked with IRQs disabled and this is explicitly checked for with WARN_ON_ONCE(). We get the batch processing outside of locked IRQ disabled sections by using some ideas from the powerpc port. Namely, we only batch inside of arch_{enter,leave}_lazy_mmu_mode() calls. If we're not in such a region, we flush TLBs synchronously. 1) Get rid of xcall_flush_tlb_pending and per-cpu type implementations. 2) Do TLB batch cross calls instead via: smp_call_function_many() tlb_pending_func() __flush_tlb_pending() 3) Batch only in lazy mmu sequences: a) Add 'active' member to struct tlb_batch b) Define __HAVE_ARCH_ENTER_LAZY_MMU_MODE c) Set 'active' in arch_enter_lazy_mmu_mode() d) Run batch and clear 'active' in arch_leave_lazy_mmu_mode() e) Check 'active' in tlb_batch_add_one() and do a synchronous flush if it's clear. 4) Add infrastructure for synchronous TLB page flushes. a) Implement __flush_tlb_page and per-cpu variants, patch as needed. b) Likewise for xcall_flush_tlb_page. c) Implement smp_flush_tlb_page() to invoke the cross-call. d) Wire up global_flush_tlb_page() to the right routine based upon CONFIG_SMP 5) It turns out that singleton batches are very common, 2 out of every 3 batch flushes have only a single entry in them. The batch flush waiting is very expensive, both because of the poll on sibling cpu completeion, as well as because passing the tlb batch pointer to the sibling cpus invokes a shared memory dereference. Therefore, in flush_tlb_pending(), if there is only one entry in the batch perform a completely asynchronous global_flush_tlb_page() instead. Reported-by: Dave Kleikamp <dave.kleikamp@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 7696/1: Fix kexec by setting outer_cache.inv_all for FeroceonIllia Ragozin2013-04-251-0/+1
| | | | | | | | | | | | | | | | | | | | | commit cd272d1ea71583170e95dde02c76166c7f9017e6 upstream. On Feroceon the L2 cache becomes non-coherent with the CPU when the L1 caches are disabled. Thus the L2 needs to be invalidated after both L1 caches are disabled. On kexec before the starting the code for relocation the kernel, the L1 caches are disabled in cpu_froc_fin (cpu_v7_proc_fin for Feroceon), but after L2 cache is never invalidated, because inv_all is not set in cache-feroceon-l2.c. So kernel relocation and decompression may has (and usually has) errors. Setting the function enables L2 invalidation and fixes the issue. Signed-off-by: Illia Ragozin <illia.ragozin@grapecom.com> Acked-by: Jason Cooper <jason@lakedaemon.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: Allow cross page reads and writes from cached translations.Andrew Honig2013-04-251-6/+4
| | | | | | | | | | | | | | | | | | commit 8f964525a121f2ff2df948dac908dcc65be21b5b upstream. This patch adds support for kvm_gfn_to_hva_cache_init functions for reads and writes that will cross a page. If the range falls within the same memslot, then this will be a fast operation. If the range is split between two memslots, then the slower kvm_read_guest and kvm_write_guest are used. Tested: Test against kvm_clock unit tests. Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: x86: Convert MSR_KVM_SYSTEM_TIME to use gfn_to_hva_cache functions ↵Andy Honig2013-04-252-27/+16
| | | | | | | | | | | | | | | | | | | | | | | (CVE-2013-1797) commit 0b79459b482e85cb7426aa7da683a9f2c97aeae1 upstream. There is a potential use after free issue with the handling of MSR_KVM_SYSTEM_TIME. If the guest specifies a GPA in a movable or removable memory such as frame buffers then KVM might continue to write to that address even after it's removed via KVM_SET_USER_MEMORY_REGION. KVM pins the page in memory so it's unlikely to cause an issue, but if the user space component re-purposes the memory previously used for the guest, then the guest will be able to corrupt that memory. Tested: Tested against kvmclock unit test Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: x86: fix for buffer overflow in handling of MSR_KVM_SYSTEM_TIME ↵Andy Honig2013-04-251-0/+5
| | | | | | | | | | | | | | | | | | | | | | (CVE-2013-1796) commit c300aa64ddf57d9c5d9c898a64b36877345dd4a9 upstream. If the guest sets the GPA of the time_page so that the request to update the time straddles a page then KVM will write onto an incorrect page. The write is done byusing kmap atomic to get a pointer to the page for the time structure and then performing a memcpy to that page starting at an offset that the guest controls. Well behaved guests always provide a 32-byte aligned address, however a malicious guest could use this to corrupt host kernel memory. Tested: Tested against kvmclock unit test. Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metalBoris Ostrovsky2013-04-165-13/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | commit 511ba86e1d386f671084b5d0e6f110bb30b8eeb2 upstream. Invoking arch_flush_lazy_mmu_mode() results in calls to preempt_enable()/disable() which may have performance impact. Since lazy MMU is not used on bare metal we can patch away arch_flush_lazy_mmu_mode() so that it is never called in such environment. [ hpa: the previous patch "Fix vmalloc_fault oops during lazy MMU updates" may cause a minor performance regression on bare metal. This patch resolves that performance regression. It is somewhat unclear to me if this is a good -stable candidate. ] Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: http://lkml.kernel.org/r/1364045796-10720-2-git-send-email-konrad.wilk@oracle.com Tested-by: Josh Boyer <jwboyer@redhat.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86, mm, paravirt: Fix vmalloc_fault oops during lazy MMU updatesSamu Kallio2013-04-161-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1160c2779b826c6f5c08e5cc542de58fd1f667d5 upstream. In paravirtualized x86_64 kernels, vmalloc_fault may cause an oops when lazy MMU updates are enabled, because set_pgd effects are being deferred. One instance of this problem is during process mm cleanup with memory cgroups enabled. The chain of events is as follows: - zap_pte_range enables lazy MMU updates - zap_pte_range eventually calls mem_cgroup_charge_statistics, which accesses the vmalloc'd mem_cgroup per-cpu stat area - vmalloc_fault is triggered which tries to sync the corresponding PGD entry with set_pgd, but the update is deferred - vmalloc_fault oopses due to a mismatch in the PUD entries The OOPs usually looks as so: ------------[ cut here ]------------ kernel BUG at arch/x86/mm/fault.c:396! invalid opcode: 0000 [#1] SMP .. snip .. CPU 1 Pid: 10866, comm: httpd Not tainted 3.6.10-4.fc18.x86_64 #1 RIP: e030:[<ffffffff816271bf>] [<ffffffff816271bf>] vmalloc_fault+0x11f/0x208 .. snip .. Call Trace: [<ffffffff81627759>] do_page_fault+0x399/0x4b0 [<ffffffff81004f4c>] ? xen_mc_extend_args+0xec/0x110 [<ffffffff81624065>] page_fault+0x25/0x30 [<ffffffff81184d03>] ? mem_cgroup_charge_statistics.isra.13+0x13/0x50 [<ffffffff81186f78>] __mem_cgroup_uncharge_common+0xd8/0x350 [<ffffffff8118aac7>] mem_cgroup_uncharge_page+0x57/0x60 [<ffffffff8115fbc0>] page_remove_rmap+0xe0/0x150 [<ffffffff8115311a>] ? vm_normal_page+0x1a/0x80 [<ffffffff81153e61>] unmap_single_vma+0x531/0x870 [<ffffffff81154962>] unmap_vmas+0x52/0xa0 [<ffffffff81007442>] ? pte_mfn_to_pfn+0x72/0x100 [<ffffffff8115c8f8>] exit_mmap+0x98/0x170 [<ffffffff810050d9>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e [<ffffffff81059ce3>] mmput+0x83/0xf0 [<ffffffff810624c4>] exit_mm+0x104/0x130 [<ffffffff8106264a>] do_exit+0x15a/0x8c0 [<ffffffff810630ff>] do_group_exit+0x3f/0xa0 [<ffffffff81063177>] sys_exit_group+0x17/0x20 [<ffffffff8162bae9>] system_call_fastpath+0x16/0x1b Calling arch_flush_lazy_mmu_mode immediately after set_pgd makes the changes visible to the consistency checks. RedHat-Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=914737 Tested-by: Josh Boyer <jwboyer@redhat.com> Reported-and-Tested-by: Krishna Raman <kraman@redhat.com> Signed-off-by: Samu Kallio <samu.kallio@aberdeencloud.com> Link: http://lkml.kernel.org/r/1364045796-10720-1-git-send-email-konrad.wilk@oracle.com Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86-32, mm: Rip out x86_32 NUMA remapping codeDave Hansen2013-04-161-161/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f03574f2d5b2d6229dcdf2d322848065f72953c7 upstream. [was already included in 3.0, but I missed the patch hunk for arch/x86/mm/numa_32.c - gregkh] This code was an optimization for 32-bit NUMA systems. It has probably been the cause of a number of subtle bugs over the years, although the conditions to excite them would have been hard to trigger. Essentially, we remap part of the kernel linear mapping area, and then sometimes part of that area gets freed back in to the bootmem allocator. If those pages get used by kernel data structures (say mem_map[] or a dentry), there's no big deal. But, if anyone ever tried to use the linear mapping for these pages _and_ cared about their physical address, bad things happen. For instance, say you passed __GFP_ZERO to the page allocator and then happened to get handed one of these pages, it zero the remapped page, but it would make a pte to the _old_ page. There are probably a hundred other ways that it could screw with things. We don't need to hang on to performance optimizations for these old boxes any more. All my 32-bit NUMA systems are long dead and buried, and I probably had access to more than most people. This code is causing real things to break today: https://lkml.org/lkml/2013/1/9/376 I looked in to actually fixing this, but it requires surgery to way too much brittle code, as well as stuff like per_cpu_ptr_to_phys(). [ hpa: Cc: this for -stable, since it is a memory corruption issue. However, an alternative is to simply mark NUMA as depends BROKEN rather than EXPERIMENTAL in the X86_32 subclause... ] Link: http://lkml.kernel.org/r/20130131005616.1C79F411@kernel.stglabs.ibm.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86-32, mm: Rip out x86_32 NUMA remapping codeDave Hansen2013-04-123-13/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f03574f2d5b2d6229dcdf2d322848065f72953c7 upstream. This code was an optimization for 32-bit NUMA systems. It has probably been the cause of a number of subtle bugs over the years, although the conditions to excite them would have been hard to trigger. Essentially, we remap part of the kernel linear mapping area, and then sometimes part of that area gets freed back in to the bootmem allocator. If those pages get used by kernel data structures (say mem_map[] or a dentry), there's no big deal. But, if anyone ever tried to use the linear mapping for these pages _and_ cared about their physical address, bad things happen. For instance, say you passed __GFP_ZERO to the page allocator and then happened to get handed one of these pages, it zero the remapped page, but it would make a pte to the _old_ page. There are probably a hundred other ways that it could screw with things. We don't need to hang on to performance optimizations for these old boxes any more. All my 32-bit NUMA systems are long dead and buried, and I probably had access to more than most people. This code is causing real things to break today: https://lkml.org/lkml/2013/1/9/376 I looked in to actually fixing this, but it requires surgery to way too much brittle code, as well as stuff like per_cpu_ptr_to_phys(). [ hpa: Cc: this for -stable, since it is a memory corruption issue. However, an alternative is to simply mark NUMA as depends BROKEN rather than EXPERIMENTAL in the X86_32 subclause... ] Link: http://lkml.kernel.org/r/20130131005616.1C79F411@kernel.stglabs.ibm.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: pSeries_lpar_hpte_remove fails from Adjunct partition being ↵Michael Wolf2013-04-121-1/+7
| | | | | | | | | | | | | | | | | | | performed before the ANDCOND test commit 9fb2640159f9d4f5a2a9d60e490482d4cbecafdb upstream. Some versions of pHyp will perform the adjunct partition test before the ANDCOND test. The result of this is that H_RESOURCE can be returned and cause the BUG_ON condition to occur. The HPTE is not removed. So add a check for H_RESOURCE, it is ok if this HPTE is not removed as pSeries_lpar_hpte_remove is looking for an HPTE to remove and not a specific HPTE to remove. So it is ok to just move on to the next slot and try again. Signed-off-by: Michael Wolf <mjw@linux.vnet.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* alpha: Add irongate_io to PCI bus resourcesJay Estabrook2013-04-121-0/+5
| | | | | | | | | | | | | | commit aa8b4be3ac049c8b1df2a87e4d1d902ccfc1f7a9 upstream. Fixes a NULL pointer dereference at boot on UP1500. Reviewed-and-Tested-by: Matt Turner <mattst88@gmail.com> Signed-off-by: Jay Estabrook <jay.estabrook@gmail.com> Signed-off-by: Matt Turner <mattst88@gmail.com> Signed-off-by: Michael Cree <mcree@orcon.net.nz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* iommu/amd: Make sure dma_ops are set for hotplug devicesJoerg Roedel2013-04-051-10/+14
| | | | | | | | | | | | | | commit c2a2876e863356b092967ea62bebdb4dd663af80 upstream. There is a bug introduced with commit 27c2127 that causes devices which are hot unplugged and then hot-replugged to not have per-device dma_ops set. This causes these devices to not function correctly. Fixed with this patch. Reported-by: Andreas Degert <andreas.degert@googlemail.com> Signed-off-by: Joerg Roedel <joro@8bytes.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: x86: invalid opcode oops on SET_SREGS with OSXSAVE bit set (CVE-2012-4461)Petr Matousek2013-04-051-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6d1068b3a98519247d8ba4ec85cd40ac136dbdf9 upstream. On hosts without the XSAVE support unprivileged local user can trigger oops similar to the one below by setting X86_CR4_OSXSAVE bit in guest cr4 register using KVM_SET_SREGS ioctl and later issuing KVM_RUN ioctl. invalid opcode: 0000 [#2] SMP Modules linked in: tun ip6table_filter ip6_tables ebtable_nat ebtables ... Pid: 24935, comm: zoog_kvm_monito Tainted: G D 3.2.0-3-686-pae EIP: 0060:[<f8b9550c>] EFLAGS: 00210246 CPU: 0 EIP is at kvm_arch_vcpu_ioctl_run+0x92a/0xd13 [kvm] EAX: 00000001 EBX: 000f387e ECX: 00000000 EDX: 00000000 ESI: 00000000 EDI: 00000000 EBP: ef5a0060 ESP: d7c63e70 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 Process zoog_kvm_monito (pid: 24935, ti=d7c62000 task=ed84a0c0 task.ti=d7c62000) Stack: 00000001 f70a1200 f8b940a9 ef5a0060 00000000 00200202 f8769009 00000000 ef5a0060 000f387e eda5c020 8722f9c8 00015bae 00000000 ed84a0c0 ed84a0c0 c12bf02d 0000ae80 ef7f8740 fffffffb f359b740 ef5a0060 f8b85dc1 0000ae80 Call Trace: [<f8b940a9>] ? kvm_arch_vcpu_ioctl_set_sregs+0x2fe/0x308 [kvm] ... [<c12bfb44>] ? syscall_call+0x7/0xb Code: 89 e8 e8 14 ee ff ff ba 00 00 04 00 89 e8 e8 98 48 ff ff 85 c0 74 1e 83 7d 48 00 75 18 8b 85 08 07 00 00 31 c9 8b 95 0c 07 00 00 <0f> 01 d1 c7 45 48 01 00 00 00 c7 45 1c 01 00 00 00 0f ae f0 89 EIP: [<f8b9550c>] kvm_arch_vcpu_ioctl_run+0x92a/0xd13 [kvm] SS:ESP 0068:d7c63e70 QEMU first retrieves the supported features via KVM_GET_SUPPORTED_CPUID and then sets them later. So guest's X86_FEATURE_XSAVE should be masked out on hosts without X86_FEATURE_XSAVE, making kvm_set_cr4 with X86_CR4_OSXSAVE fail. Userspaces that allow specifying guest cpuid with X86_FEATURE_XSAVE even on hosts that do not support it, might be susceptible to this attack from inside the guest as well. Allow setting X86_CR4_OSXSAVE bit only if host has XSAVE support. Signed-off-by: Petr Matousek <pmatouse@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: Ensure all vcpus are consistent with in-kernel irqchip settingsAvi Kivity2013-04-052-0/+13
| | | | | | | | | | | | | | | | | | | | | | commit 3e515705a1f46beb1c942bb8043c16f8ac7b1e9e upstream. If some vcpus are created before KVM_CREATE_IRQCHIP, then irqchip_in_kernel() and vcpu->arch.apic will be inconsistent, leading to potential NULL pointer dereferences. Fix by: - ensuring that no vcpus are installed when KVM_CREATE_IRQCHIP is called - ensuring that a vcpu has an apic if it is installed after KVM_CREATE_IRQCHIP This is somewhat long winded because vcpu->arch.apic is created without kvm->lock held. Based on earlier patch by Michael Ellerman. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: x86: Prevent starting PIT timers in the absence of irqchip supportJan Kiszka2013-04-051-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | commit 0924ab2cfa98b1ece26c033d696651fd62896c69 upstream. User space may create the PIT and forgets about setting up the irqchips. In that case, firing PIT IRQs will crash the host: BUG: unable to handle kernel NULL pointer dereference at 0000000000000128 IP: [<ffffffffa10f6280>] kvm_set_irq+0x30/0x170 [kvm] ... Call Trace: [<ffffffffa11228c1>] pit_do_work+0x51/0xd0 [kvm] [<ffffffff81071431>] process_one_work+0x111/0x4d0 [<ffffffff81071bb2>] worker_thread+0x152/0x340 [<ffffffff81075c8e>] kthread+0x7e/0x90 [<ffffffff815a4474>] kernel_thread_helper+0x4/0x10 Prevent this by checking the irqchip mode before starting a timer. We can't deny creating the PIT if the irqchips aren't set up yet as current user land expects this order to work. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: Clean up error handling during VCPU creationJan Kiszka2013-04-051-5/+0
| | | | | | | | | | | | | | commit d780592b99d7d8a5ff905f6bacca519d4a342c76 upstream. So far kvm_arch_vcpu_setup is responsible for freeing the vcpu struct if it fails. Move this confusing resonsibility back into the hands of kvm_vm_ioctl_create_vcpu. Only kvm_arch_vcpu_setup of x86 is affected, all other archs cannot fail. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* signal: Define __ARCH_HAS_SA_RESTORER so we know whether to clear sa_restorerBen Hutchings2013-04-0512-0/+13
| | | | | | | | | | | | | | Vaguely based on upstream commit 574c4866e33d 'consolidate kernel-side struct sigaction declarations'. flush_signal_handlers() needs to know whether sigaction::sa_restorer is defined, not whether SA_RESTORER is defined. Define the __ARCH_HAS_SA_RESTORER macro to indicate this. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86-64: Fix the failure case in copy_user_handle_tail()CQ Tang2013-03-281-2/+2
| | | | | | | | | | | | | | | | | commit 66db3feb486c01349f767b98ebb10b0c3d2d021b upstream. The increment of "to" in copy_user_handle_tail() will have incremented before a failure has been noted. This causes us to skip a byte in the failure case. Only do the increment when assured there is no failure. Signed-off-by: CQ Tang <cq.tang@intel.com> Link: http://lkml.kernel.org/r/20130318150221.8439.993.stgit@phlsvslse11.ph.intel.com Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* s390/mm: fix flush_tlb_kernel_range()Heiko Carstens2013-03-201-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | commit f6a70a07079518280022286a1dceb797d12e1edf upstream. Our flush_tlb_kernel_range() implementation calls __tlb_flush_mm() with &init_mm as argument. __tlb_flush_mm() however will only flush tlbs for the passed in mm if its mm_cpumask is not empty. For the init_mm however its mm_cpumask has never any bits set. Which in turn means that our flush_tlb_kernel_range() implementation doesn't work at all. This can be easily verified with a vmalloc/vfree loop which allocates a page, writes to it and then frees the page again. A crash will follow almost instantly. To fix this remove the cpumask_empty() check in __tlb_flush_mm() since there shouldn't be too many mms with a zero mm_cpumask, besides the init_mm of course. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* perf,x86: fix wrmsr_on_cpu() warning on suspend/resumeLinus Torvalds2013-03-201-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | commit 2a6e06b2aed6995af401dcd4feb5e79a0c7ea554 upstream. Commit 1d9d8639c063 ("perf,x86: fix kernel crash with PEBS/BTS after suspend/resume") fixed a crash when doing PEBS performance profiling after resuming, but in using init_debug_store_on_cpu() to restore the DS_AREA mtrr it also resulted in a new WARN_ON() triggering. init_debug_store_on_cpu() uses "wrmsr_on_cpu()", which in turn uses CPU cross-calls to do the MSR update. Which is not really valid at the early resume stage, and the warning is quite reasonable. Now, it all happens to _work_, for the simple reason that smp_call_function_single() ends up just doing the call directly on the CPU when the CPU number matches, but we really should just do the wrmsr() directly instead. This duplicates the wrmsr() logic, but hopefully we can just remove the wrmsr_on_cpu() version eventually. Reported-and-tested-by: Parag Warudkar <parag.lkml@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* perf,x86: fix kernel crash with PEBS/BTS after suspend/resumeStephane Eranian2013-03-202-0/+10
| | | | | | | | | | | | | | | | | | | | | commit 1d9d8639c063caf6efc2447f5f26aa637f844ff6 upstream. This patch fixes a kernel crash when using precise sampling (PEBS) after a suspend/resume. Turns out the CPU notifier code is not invoked on CPU0 (BP). Therefore, the DS_AREA (used by PEBS) is not restored properly by the kernel and keeps it power-on/resume value of 0 causing any PEBS measurement to crash when running on CPU0. The workaround is to add a hook in the actual resume code to restore the DS Area MSR value. It is invoked for all CPUS. So for all but CPU0, the DS_AREA will be restored twice but this is harmless. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Shuah Khan <shuah.khan@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* powerpc: Fix cputable entry for 970MP rev 1.0Benjamin Herrenschmidt2013-03-201-1/+1
| | | | | | | | | | | | | | commit d63ac5f6cf31c8a83170a9509b350c1489a7262b upstream. Commit 44ae3ab3358e962039c36ad4ae461ae9fb29596c forgot to update the entry for the 970MP rev 1.0 processor when moving some CPU features bits to the MMU feature bit mask. This breaks booting on some rare G5 models using that chip revision. Reported-by: Phileas Fogg <phileas-fogg@mail.ru> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: fix scheduling while atomic warning in alignment handling codeRussell King2013-03-141-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b255188f90e2bade1bd11a986dd1ca4861869f4d upstream. Paolo Pisati reports that IPv6 triggers this warning: BUG: scheduling while atomic: swapper/0/0/0x40000100 Modules linked in: [<c001b1c4>] (unwind_backtrace+0x0/0xf0) from [<c0503c5c>] (__schedule_bug+0x48/0x5c) [<c0503c5c>] (__schedule_bug+0x48/0x5c) from [<c0508608>] (__schedule+0x700/0x740) [<c0508608>] (__schedule+0x700/0x740) from [<c007007c>] (__cond_resched+0x24/0x34) [<c007007c>] (__cond_resched+0x24/0x34) from [<c05086dc>] (_cond_resched+0x3c/0x44) [<c05086dc>] (_cond_resched+0x3c/0x44) from [<c0021f6c>] (do_alignment+0x178/0x78c) [<c0021f6c>] (do_alignment+0x178/0x78c) from [<c00083e0>] (do_DataAbort+0x34/0x98) [<c00083e0>] (do_DataAbort+0x34/0x98) from [<c0509a60>] (__dabt_svc+0x40/0x60) Exception stack(0xc0763d70 to 0xc0763db8) 3d60: e97e805e e97e806e 2c000000 11000000 3d80: ea86bb00 0000002c 00000011 e97e807e c076d2a8 e97e805e e97e806e 0000002c 3da0: 3d000000 c0763dbc c04b98fc c02a8490 00000113 ffffffff [<c0509a60>] (__dabt_svc+0x40/0x60) from [<c02a8490>] (__csum_ipv6_magic+0x8/0xc8) Fix this by using probe_kernel_address() stead of __get_user(). Reported-by: Paolo Pisati <p.pisati@gmail.com> Tested-by: Paolo Pisati <p.pisati@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: VFP: fix emulation of second VFP instructionRussell King2013-03-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5e4ba617c1b584b2e376f31a63bd4e734109318a upstream. Martin Storsjö reports that the sequence: ee312ac1 vsub.f32 s4, s3, s2 ee702ac0 vsub.f32 s5, s1, s0 e59f0028 ldr r0, [pc, #40] ee111a90 vmov r1, s3 on Raspberry Pi (implementor 41 architecture 1 part 20 variant b rev 5) where s3 is a denormal and s2 is zero results in incorrect behaviour - the instruction "vsub.f32 s5, s1, s0" is not executed: VFP: bounce: trigger ee111a90 fpexc d0000780 VFP: emulate: INST=0xee312ac1 SCR=0x00000000 ... As we can see, the instruction triggering the exception is the "vmov" instruction, and we emulate the "vsub.f32 s4, s3, s2" but fail to properly take account of the FPEXC_FP2V flag in FPEXC. This is because the test for the second instruction register being valid is bogus, and will always skip emulation of the second instruction. Reported-by: Martin Storsjö <martin@martin.st> Tested-by: Martin Storsjö <martin@martin.st> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* s390/kvm: Fix store status for ACRS/FPRS fixJiri Slaby2013-03-041-1/+1
| | | | | | | | | | | | | | | In 3.0.67, commit 58c9ce6fad8e00d9726447f939fe7e78e2aec891 (s390/kvm: Fix store status for ACRS/FPRS), upstream commit 15bc8d8457875f495c59d933b05770ba88d1eacb, added a call to save_access_regs to save ACRS. But we do not have ARCS in kvm_run in 3.0 yet, so this results in: arch/s390/kvm/kvm-s390.c: In function 'kvm_s390_vcpu_store_status': arch/s390/kvm/kvm-s390.c:593: error: 'struct kvm_run' has no member named 's' Fix it by saving guest_acrs which is where ARCS are in 3.0. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/apic: Work around boot failure on HP ProLiant DL980 G7 Server systemsStoney Wang2013-03-041-5/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit cb214ede7657db458fd0b2a25ea0b28dbf900ebc upstream. When a HP ProLiant DL980 G7 Server boots a regular kernel, there will be intermittent lost interrupts which could result in a hang or (in extreme cases) data loss. The reason is that this system only supports x2apic physical mode, while the kernel boots with a logical-cluster default setting. This bug can be worked around by specifying the "x2apic_phys" or "nox2apic" boot option, but we want to handle this system without requiring manual workarounds. The BIOS sets ACPI_FADT_APIC_PHYSICAL in FADT table. As all apicids are smaller than 255, BIOS need to pass the control to the OS with xapic mode, according to x2apic-spec, chapter 2.9. Current code handle x2apic when BIOS pass with xapic mode enabled: When user specifies x2apic_phys, or FADT indicates PHYSICAL: 1. During madt oem check, apic driver is set with xapic logical or xapic phys driver at first. 2. enable_IR_x2apic() will enable x2apic_mode. 3. if user specifies x2apic_phys on the boot line, x2apic_phys_probe() will install the correct x2apic phys driver and use x2apic phys mode. Otherwise it will skip the driver will let x2apic_cluster_probe to take over to install x2apic cluster driver (wrong one) even though FADT indicates PHYSICAL, because x2apic_phys_probe does not check FADT PHYSICAL. Add checking x2apic_fadt_phys in x2apic_phys_probe() to fix the problem. Signed-off-by: Stoney Wang <song-bo.wang@hp.com> [ updated the changelog and simplified the code ] Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Zhang Lin-Bao <Linbao.zhang@hp.com> [ make a patch specially for 3.0.66] Link: http://lkml.kernel.org/r/1360263182-16226-1-git-send-email-yinghai@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86: Do not leak kernel page mapping locationsKees Cook2013-03-041-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e575a86fdc50d013bf3ad3aa81d9100e8e6cc60d upstream. Without this patch, it is trivial to determine kernel page mappings by examining the error code reported to dmesg[1]. Instead, declare the entire kernel memory space as a violation of a present page. Additionally, since show_unhandled_signals is enabled by default, switch branch hinting to the more realistic expectation, and unobfuscate the setting of the PF_PROT bit to improve readability. [1] http://vulnfactory.org/blog/2013/02/06/a-linux-memory-trick/ Reported-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Suggested-by: Brad Spengler <spender@grsecurity.net> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20130207174413.GA12485@www.outflux.net Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: CAI Qian <caiqian@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86: Make sure we can boot in the case the BDA contains pure garbageH. Peter Anvin2013-03-041-19/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7c10093692ed2e6f318387d96b829320aa0ca64c upstream. On non-BIOS platforms it is possible that the BIOS data area contains garbage instead of being zeroed or something equivalent (firmware people: we are talking of 1.5K here, so please do the sane thing.) We need on the order of 20-30K of low memory in order to boot, which may grow up to < 64K in the future. We probably want to avoid the lowest of the low memory. At the same time, it seems extremely unlikely that a legitimate EBDA would ever reach down to the 128K (which would require it to be over half a megabyte in size.) Thus, pick 128K as the cutoff for "this is insane, ignore." We may still end up reserving a bunch of extra memory on the low megabyte, but that is not really a major issue these days. In the worst case we lose 512K of RAM. This code really should be merged with trim_bios_range() in arch/x86/kernel/setup.c, but that is a bigger patch for a later merge window. Reported-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Matt Fleming <matt.fleming@intel.com> Link: http://lkml.kernel.org/n/tip-oebml055yyfm8yxmria09rja@git.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* iommu/amd: Initialize device table after dma_opsJoerg Roedel2013-03-041-3/+7
| | | | | | | | | | | | | | | | commit f528d980c17b8714aedc918ba86e058af914d66b upstream. When dma_ops are initialized the unity mappings are created. The init_device_table_dma() function makes sure DMA from all devices is blocked by default. This opens a short window in time where DMA to unity mapped regions is blocked by the IOMMU. Make sure this does not happen by initializing the device table after dma_ops. Signed-off-by: Joerg Roedel <joro@8bytes.org> Signed-off-by: Shuah Khan <shuah.khan@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Purge existing TLB entries in set_pte_at and ptep_set_wrprotectJohn David Anglin2013-02-282-3/+28
| | | | | | | | | | | | | | | | | commit 7139bc1579901b53db7e898789e916ee2fb52d78 upstream. This patch goes a long way toward fixing the minifail bug, and it  significantly improves the stability of SMP machines such as the rp3440.  When write  protecting a page for COW, we need to purge the existing translation.  Otherwise, the COW break doesn't occur as expected because the TLB may still have a stale entry which allows writes. [jejb: fix up checkpatch errors] Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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