- 03 3月, 2013 21 次提交
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由 James Hogan 提交于
Add time keeping code for metag. Meta hardware threads have 2 timers. The background timer (TXTIMER) is used as a free-running time base, and the interrupt timer (TXTIMERI) is used for the timer interrupt. Both counters traditionally count at approximately 1MHz. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Cc: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de>
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由 James Hogan 提交于
The ptrace interface for metag provides access to some core register sets using the PTRACE_GETREGSET and PTRACE_SETREGSET operations. The details of the internal context structures is abstracted into user API structures to both ease use and allow flexibility to change the internal context layouts. Copyin and copyout functions for these register sets are exposed to allow signal handling code to use them to copy to and from the signal context. struct user_gp_regs (NT_PRSTATUS) provides access to the core general purpose register context. struct user_cb_regs (NT_METAG_CBUF) provides access to the TXCATCH* registers which contains information abuot a memory fault, unaligned access error or watchpoint. This can be modified to alter the way the fault is replayed on resume ("catch replay"), or to prevent the replay taking place. struct user_rp_state (NT_METAG_RPIPE) provides access to the state of the Meta read pipeline which can be used to hide memory latencies in hand optimised data loops. Extended DSP register state, DSP RAM, and hardware breakpoint registers aren't yet exposed through ptrace. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Tony Lindgren <tony@atomide.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
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由 James Hogan 提交于
Add device tree files to arch/metag. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Reviewed-by: NVineet Gupta <vgupta@synopsys.com>
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由 James Hogan 提交于
Add signal handling code for metag. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Cc: Al Viro <viro@zeniv.linux.org.uk>
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由 James Hogan 提交于
Add some TCM support Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Add huge TLB support to the metag architecture. Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Meta has instructions for accessing: - bytes - GETB (1 byte) - words - GETW (2 bytes) - doublewords - GETD (4 bytes) - longwords - GETL (8 bytes) All accesses must be aligned. Unaligned accesses can be detected and made to fault on Meta2, however it isn't possible to fix up unaligned writes so we don't bother fixing up reads either. This patch adds metag memory handling code including: - I/O memory (io.h, ioremap.c): Actually any virtual memory can be accessed with these helpers. A part of the non-MMUable address space is used for memory mapped I/O. The ioremap() function is implemented one to one for non-MMUable addresses. - User memory (uaccess.h, usercopy.c): User memory is directly accessible from privileged code. - Kernel memory (maccess.c): probe_kernel_write() needs to be overwridden to use the I/O functions when doing a simple aligned write to non-writecombined memory, otherwise the write may be split by the generic version. Note that due to the fact that a portion of the virtual address space is non-MMUable, and therefore always maps directly to the physical address space, metag specific I/O functions are made available (metag_in32, metag_out32 etc). These cast the address argument to a pointer so that they can be used with raw physical addresses. These accessors are only to be used for accessing fixed core Meta architecture registers in the non-MMU region, and not for any SoC/peripheral registers. Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Add memory management files for metag. Meta's 32bit virtual address space is split into two halves: - local (0x08000000-0x7fffffff): traditionally local to a hardware thread and incoherent between hardware threads. Each hardware thread has it's own local MMU table. On Meta2 the local space can be globally coherent (GCOn) if the cache partitions coincide. - global (0x88000000-0xffff0000): coherent and traditionally global between hardware threads. On Meta2, each hardware thread has it's own global MMU table. The low 128MiB of each half is non-MMUable and maps directly to the physical address space: - 0x00010000-0x07ffffff: contains Meta core registers and maps SoC bus - 0x80000000-0x87ffffff: contains low latency global core memories Linux usually further splits the local virtual address space like this: - 0x08000000-0x3fffffff: user mappings - 0x40000000-0x7fffffff: kernel mappings Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Add cache and TLB handling code for metag, including the required callbacks used by MM switches and DMA operations. Caches can be partitioned between the hardware threads and the global space, however this is usually configured by the bootloader so Linux doesn't make any changes to this configuration. TLBs aren't configurable, so only need consideration to flush them. On Meta1 the L1 cache was VIVT which required a full flush on MM switch. Meta2 has a VIPT L1 cache so it doesn't require the full flush on MM switch. Meta2 can also have a writeback L2 with hardware prefetch which requires some special handling. Support is optional, and the L2 can be detected and initialised by Linux. Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Add source files from the Thread Binary Interface (TBI) library which provides useful low level operations and traps/context management. Among other things it handles interrupt/exception/syscall entry (in tbipcx.S). Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Add the main header for the Thread Binary Interface (TBI) library which provides useful low level operations and trap/context management. Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Add boot code for metag. Due to the multi-threaded nature of Meta it is not uncommon for an RTOS or bare metal application to be started on other hardware threads by the bootloader. Since there is a single MMU switch which affects all threads, the MMU is traditionally configured by the bootloader prior to starting Linux. The bootloader passes a structure to Linux which among other things contains information about memory regions which have been mapped. Linux then assumes control of the local heap memory region. A kernel arguments string pointer or a flattened device tree pointer can be provided in the third argument. Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Add the header <asm/metag_mem.h> describing addresses, fields, and bits of various core memory mapped registers in the low non-MMU region. Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Add a couple of header files containing core architecture constants. The first (<asm/metag_isa.h>) contains some constants relating to the instruction set, such as values to give to the CACHEW and CACHER instructions. The second (<asm/metag_regs.h>) contains constants for the core register units directly accessible to various instructions, and for the registers, fields, and bits in those units. The main units described are the control unit (CT.*), the trigger unit (TR.*), and the run-time trace unit (TT.*). Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
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由 James Hogan 提交于
Add MAINTAINERS entry for the metag architecture port. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mauro Carvalho Chehab <mchehab@redhat.com> Cc: Cesar Eduardo Barros <cesarb@cesarb.net> Cc: Joe Perches <joe@perches.com> Cc: "David S. Miller" <davem@davemloft.net>
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由 James Hogan 提交于
Some 32 bit architectures require 64 bit values to be aligned (for example Meta which has 64 bit read/write instructions). These require 8 byte alignment of event data too, so use !CONFIG_HAVE_64BIT_ALIGNED_ACCESS instead of !CONFIG_64BIT || CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to decide alignment, and align buffer_data_page::data accordingly. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> (previous version subtly different)
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由 James Hogan 提交于
On 64 bit architectures with no efficient unaligned access, padding and explicit alignment must be added in various places to prevent unaligned 64bit accesses (such as taskstats and trace ring buffer). However this also needs to apply to 32 bit architectures with 64 bit accesses requiring alignment such as metag. This is solved by adding a new Kconfig symbol HAVE_64BIT_ALIGNED_ACCESS which defaults to 64BIT && !HAVE_EFFICIENT_UNALIGNED_ACCESS, and can be explicitly selected by METAG and any other relevant architectures. This can be used in various places to determine whether 64bit alignment is required. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Paris <eparis@redhat.com> Cc: Will Drewry <wad@chromium.org>
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由 James Hogan 提交于
The commit "binfmt_elf: cleanups" (f670d0ec) removed an ifndef elf_map but this breaks compilation for metag which does define elf_map. This adds the ifndef back in as it was before, but does not affect the other cleanups made by that patch. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Acked-by: NMikael Pettersson <mikpe@it.uu.se>
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由 James Hogan 提交于
Some architectures have symbol prefixes and set CONFIG_SYMBOL_PREFIX, but this wasn't taken into account by the generic cond_syscall. It's easy enough to fix in a generic fashion, so add the symbol prefix to symbol names in cond_syscall when CONFIG_SYMBOL_PREFIX is set. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Acked-by: NArnd Bergmann <arnd@arndb.de> Acked-by: NMike Frysinger <vapier@gentoo.org>
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由 James Hogan 提交于
Make asm-generic/io.h check CONFIG_VIRT_TO_BUS before defining virt_to_bus() and bus_to_virt(), otherwise it's easy to accidentally have a silently failing incorrect direct mapped definition rather then no definition at all. Signed-off-by: NJames Hogan <james.hogan@imgtec.com> Acked-by: NArnd Bergmann <arnd@arndb.de>
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- 19 2月, 2013 3 次提交
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由 Linus Torvalds 提交于
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git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input由 Linus Torvalds 提交于
Pull input subsystem fixes from Dmitry Torokhov: "Two small driver fixups and a documentation update for managed input devices" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: wacom - fix wacom_set_report retry logic Input: document that unregistering managed devices is not necessary Input: lm8323 - fix checking PWM interrupt status
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由 Linus Torvalds 提交于
Commit c060f943 ("mm: use aligned zone start for pfn_to_bitidx calculation") fixed out calculation of the index into the pageblock bitmap when a !SPARSEMEM zome was not aligned to pageblock_nr_pages. However, the _allocation_ of that bitmap had never taken this alignment requirement into accout, so depending on the exact size and alignment of the zone, the use of that index could then access past the allocation, resulting in some very subtle memory corruption. This was reported (and bisected) by Ingo Molnar: one of his random config builds would hang with certain very specific kernel command line options. In the meantime, commit c060f943 has been marked for stable, so this fix needs to be back-ported to the stable kernels that backported the commit to use the right alignment. Bisected-and-tested-by: NIngo Molnar <mingo@kernel.org> Acked-by: NMel Gorman <mgorman@suse.de> Cc: stable@kernel.org Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 16 2月, 2013 7 次提交
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由 Linus Torvalds 提交于
Merge tag 'stable/for-linus-3.8-rc7-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull xen fixes from Konrad Rzeszutek Wilk: "Two fixes: - A simple bug-fix for redundant NULL check. - CVE-2013-0228/XSA-42: x86/xen: don't assume %ds is usable in xen_iret for 32-bit PVOPS and two reverts: - Revert the PVonHVM kexec. The patch introduces a regression with older hypervisor stacks, such as Xen 4.1." * tag 'stable/for-linus-3.8-rc7-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: Revert "xen PVonHVM: use E820_Reserved area for shared_info" Revert "xen/PVonHVM: fix compile warning in init_hvm_pv_info" xen: remove redundant NULL check before unregister_and_remove_pcpu(). x86/xen: don't assume %ds is usable in xen_iret for 32-bit PVOPS.
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由 Mauro Carvalho Chehab 提交于
As reported by Klaus Schmidinger: "In VDR I use an ioctl() call with FE_READ_UNCORRECTED_BLOCKS on a device (using stb0899). After this call I check 'errno' for EOPNOTSUPP to determine whether this device supports this call. This used to work just fine, until a few months ago I noticed that my devices using stb0899 didn't display their signal quality in VDR's OSD any more. After further investigation I found that ioctl(FE_READ_UNCORRECTED_BLOCKS) no longer returns EOPNOTSUPP, but rather ENOTTY. And since I stop getting the signal quality in case any unknown errno value appears, this broke my signal quality query function." While the changes reflect what is there at: http://comments.gmane.org/gmane.linux.kernel/1235728 it does cause regression on userspace. So, revert it to stop the damage. This reverts commit 177ffe50 ("[media] dvb_frontend: return -ENOTTY for unimplement IOCTL"). Reported-by: NKlaus Schmidinger <Klaus.Schmidinger@tvdr.de> Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc由 Linus Torvalds 提交于
Pull sparc fixes from David Miller: "A couple small fixes for sparc including some THP brown-paper-bag material: 1) During the merging of all the THP support for various architectures, sparc missed adding a HAVE_ARCH_TRANSPARENT_HUGEPAGE to it's Kconfig, oops. 2) Sparc needs to be mindful of hugepages in get_user_pages_fast(). 3) Fix memory leak in SBUS probe, from Cong Ding. 4) The sunvdc virtual disk client driver has a test of the bitmask of vdisk server supported operations which was off by one bit" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc: sunvdc: Fix off-by-one in generic_request(). sparc64: Fix get_user_pages_fast() wrt. THP. sparc64: Add missing HAVE_ARCH_TRANSPARENT_HUGEPAGE. sparc: kernel/sbus.c: fix memory leakage
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip由 Linus Torvalds 提交于
Pull one more x86 fix from Peter Anvin: "Sigh. One more patch in the "please don't brick my Samsung" series" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi: Clear EFI_RUNTIME_SERVICES rather than EFI_BOOT by "noefi" boot parameter
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git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci由 Linus Torvalds 提交于
Pull PCI fix from Bjorn Helgaas: "This is another fix for v3.8. It fixes an oops that happens when a Thunderbolt adapter is unplugged (remove device, poll for PME events on no-longer-existing device, oops)." * tag '3.8-pci-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: PCI/PM: Clean up PME state when removing a device
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git://gitorious.org/linux-omap-dss2/linux由 Linus Torvalds 提交于
Pull omapdss fixes from Tomi Valkeinen: "It'd be great if these two late fixes would still make it into 3.8. The other one fixes ARM kernel compilation when using 'allyesconfig', and the other makes DPI displays function again on OMAP3630 boards: - Fix ARM compilation with "allyesconfig" (omapdrm: fix the dependency to omapdss) - fix DPI displays on OMAP3630 (OMAPDSS: add FEAT_DPI_USES_VDDS_DSI to omap3630_dss_feat_list)" * tag 'omapdss-for-3.8-rc8' of git://gitorious.org/linux-omap-dss2/linux: omapdrm: fix the dependency to omapdss OMAPDSS: add FEAT_DPI_USES_VDDS_DSI to omap3630_dss_feat_list
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git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux由 Linus Torvalds 提交于
Pull i2c maintainer info update from Wolfram Sang: "Since my old email and repos are not working anymore, and this already caused some confusion, I think a MAINTAINERS update for 3.8 is helpful. So, people trying I2C with the new kernel can properly reach me and find my repos." * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: MAINTAINERS: change my email and repos
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- 15 2月, 2013 3 次提交
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由 Konrad Rzeszutek Wilk 提交于
This reverts commit 9d02b43d. We are doing this b/c on 32-bit PVonHVM with older hypervisors (Xen 4.1) it ends up bothing up the start_info. This is bad b/c we use it for the time keeping, and the timekeeping code loops forever - as the version field never changes. Olaf says to revert it, so lets do that. Acked-by: NOlaf Hering <olaf@aepfle.de> Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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由 Konrad Rzeszutek Wilk 提交于
This reverts commit a7be94ac. Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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由 David S. Miller 提交于
The 'operations' bitmap corresponds one-for-one with the operation codes, no adjustment is necessary. Reported-by: NMark Kettenis <mark.kettenis@xs4all.nl> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 14 2月, 2013 6 次提交
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由 Tomi Valkeinen 提交于
omapdrm uses "select" in Kconfig to enable omapdss. This doesn't work correctly, as "select" forces omapdss to be enabled in the config even if it normally could not be enabled because of missing Kconfig dependencies. This causes a build break on ARM, when using allyesconfig: drivers/video/omap2/dss/dss.c: In function 'dss_calc_clock_div': drivers/video/omap2/dss/dss.c:572:20: error: 'CONFIG_OMAP2_DSS_MIN_FCK_PER_PCK' undeclared (first use in this function) drivers/video/omap2/dss/dss.c:572:20: note: each undeclared identifier is reported only once for each function it appears in Instead of using select, this patch changes omapdrm to use "depend on". Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
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由 NeilBrown 提交于
commit 195e672a OMAPDSS: DPI: Remove cpu_is_xxxx checks made the mistake of assuming that cpu_is_omap34xx() is exclusive of other cpu_is_* predicates whereas it includes cpu_is_omap3630(). So on an omap3630, code that was previously enabled by if (cpu_is_omap34xx()) is now disabled as dss_has_feature(FEAT_DPI_USES_VDDS_DSI) fails. So add FEAT_DPI_USES_VDDS_DSI to omap3630_dss_feat_list. Cc: Chandrabhanu Mahapatra <cmahapatra@ti.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Signed-off-by: NNeilBrown <neilb@suse.de> Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
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由 Satoru Takeuchi 提交于
There was a serious problem in samsung-laptop that its platform driver is designed to run under BIOS and running under EFI can cause the machine to become bricked or can cause Machine Check Exceptions. Discussion about this problem: https://bugs.launchpad.net/ubuntu-cdimage/+bug/1040557 https://bugzilla.kernel.org/show_bug.cgi?id=47121 The patches to fix this problem: efi: Make 'efi_enabled' a function to query EFI facilities 83e68189 samsung-laptop: Disable on EFI hardware e0094244 Unfortunately this problem comes back again if users specify "noefi" option. This parameter clears EFI_BOOT and that driver continues to run even if running under EFI. Refer to the document, this parameter should clear EFI_RUNTIME_SERVICES instead. Documentation/kernel-parameters.txt: =============================================================================== ... noefi [X86] Disable EFI runtime services support. ... =============================================================================== Documentation/x86/x86_64/uefi.txt: =============================================================================== ... - If some or all EFI runtime services don't work, you can try following kernel command line parameters to turn off some or all EFI runtime services. noefi turn off all EFI runtime services ... =============================================================================== Signed-off-by: NSatoru Takeuchi <takeuchi_satoru@jp.fujitsu.com> Link: http://lkml.kernel.org/r/511C2C04.2070108@jp.fujitsu.com Cc: Matt Fleming <matt.fleming@intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Cyril Roelandt 提交于
unregister_and_remove_pcpu on a NULL pointer is a no-op, so the NULL check in sync_pcpu can be removed. Signed-off-by: NCyril Roelandt <tipecaml@gmail.com> Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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由 Jan Beulich 提交于
This fixes CVE-2013-0228 / XSA-42 Drew Jones while working on CVE-2013-0190 found that that unprivileged guest user in 32bit PV guest can use to crash the > guest with the panic like this: ------------- general protection fault: 0000 [#1] SMP last sysfs file: /sys/devices/vbd-51712/block/xvda/dev Modules linked in: sunrpc ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ipv6 xen_netfront ext4 mbcache jbd2 xen_blkfront dm_mirror dm_region_hash dm_log dm_mod [last unloaded: scsi_wait_scan] Pid: 1250, comm: r Not tainted 2.6.32-356.el6.i686 #1 EIP: 0061:[<c0407462>] EFLAGS: 00010086 CPU: 0 EIP is at xen_iret+0x12/0x2b EAX: eb8d0000 EBX: 00000001 ECX: 08049860 EDX: 00000010 ESI: 00000000 EDI: 003d0f00 EBP: b77f8388 ESP: eb8d1fe0 DS: 0000 ES: 007b FS: 0000 GS: 00e0 SS: 0069 Process r (pid: 1250, ti=eb8d0000 task=c2953550 task.ti=eb8d0000) Stack: 00000000 0027f416 00000073 00000206 b77f8364 0000007b 00000000 00000000 Call Trace: Code: c3 8b 44 24 18 81 4c 24 38 00 02 00 00 8d 64 24 30 e9 03 00 00 00 8d 76 00 f7 44 24 08 00 00 02 80 75 33 50 b8 00 e0 ff ff 21 e0 <8b> 40 10 8b 04 85 a0 f6 ab c0 8b 80 0c b0 b3 c0 f6 44 24 0d 02 EIP: [<c0407462>] xen_iret+0x12/0x2b SS:ESP 0069:eb8d1fe0 general protection fault: 0000 [#2] ---[ end trace ab0d29a492dcd330 ]--- Kernel panic - not syncing: Fatal exception Pid: 1250, comm: r Tainted: G D --------------- 2.6.32-356.el6.i686 #1 Call Trace: [<c08476df>] ? panic+0x6e/0x122 [<c084b63c>] ? oops_end+0xbc/0xd0 [<c084b260>] ? do_general_protection+0x0/0x210 [<c084a9b7>] ? error_code+0x73/ ------------- Petr says: " I've analysed the bug and I think that xen_iret() cannot cope with mangled DS, in this case zeroed out (null selector/descriptor) by either xen_failsafe_callback() or RESTORE_REGS because the corresponding LDT entry was invalidated by the reproducer. " Jan took a look at the preliminary patch and came up a fix that solves this problem: "This code gets called after all registers other than those handled by IRET got already restored, hence a null selector in %ds or a non-null one that got loaded from a code or read-only data descriptor would cause a kernel mode fault (with the potential of crashing the kernel as a whole, if panic_on_oops is set)." The way to fix this is to realize that the we can only relay on the registers that IRET restores. The two that are guaranteed are the %cs and %ss as they are always fixed GDT selectors. Also they are inaccessible from user mode - so they cannot be altered. This is the approach taken in this patch. Another alternative option suggested by Jan would be to relay on the subtle realization that using the %ebp or %esp relative references uses the %ss segment. In which case we could switch from using %eax to %ebp and would not need the %ss over-rides. That would also require one extra instruction to compensate for the one place where the register is used as scaled index. However Andrew pointed out that is too subtle and if further work was to be done in this code-path it could escape folks attention and lead to accidents. Reviewed-by: NPetr Matousek <pmatouse@redhat.com> Reported-by: NPetr Matousek <pmatouse@redhat.com> Reviewed-by: NAndrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: NJan Beulich <jbeulich@suse.com> Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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由 David S. Miller 提交于
Mostly mirrors the s390 logic, as unlike x86 we don't need the SetPageReferenced() bits. On sparc64 we also lack a user/privileged bit in the huge PMDs. In order to make this work for THP and non-THP builds, some header file adjustments were necessary. Namely, provide the PMD_HUGE_* bit defines and the pmd_large() inline unconditionally rather than protected by TRANSPARENT_HUGEPAGE. Reported-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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