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* x86/ioapic: Fix incorrect pointers in ioapic_setup_resources()Rui Wang2016-06-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On a 4-socket Brickland system, hot-removing one ioapic is fine. Hot-removing the 2nd one causes panic in mp_unregister_ioapic() while calling release_resource(). It is because the iomem_res pointer has already been released when removing the first ioapic. To explain the use of &res[num] here: res is assigned to ioapic_resources, and later in ioapic_insert_resources() we do: struct resource *r = ioapic_resources; for_each_ioapic(i) { insert_resource(&iomem_resource, r); r++; } Here 'r' is treated as an arry of 'struct resource', and the r++ ensures that each element of the array is inserted separately. Thus we should call release_resouce() on each element at &res[num]. Fix it by assigning the correct pointers to ioapics[i].iomem_res in ioapic_setup_resources(). Signed-off-by: Rui Wang <rui.y.wang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: tony.luck@intel.com Cc: linux-pci@vger.kernel.org Cc: rjw@rjwysocki.net Cc: linux-acpi@vger.kernel.org Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1465369193-4816-3-git-send-email-rui.y.wang@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* printk/nmi: generic solution for safe printk in NMIPetr Mladek2016-05-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | printk() takes some locks and could not be used a safe way in NMI context. The chance of a deadlock is real especially when printing stacks from all CPUs. This particular problem has been addressed on x86 by the commit a9edc8809328 ("x86/nmi: Perform a safe NMI stack trace on all CPUs"). The patchset brings two big advantages. First, it makes the NMI backtraces safe on all architectures for free. Second, it makes all NMI messages almost safe on all architectures (the temporary buffer is limited. We still should keep the number of messages in NMI context at minimum). Note that there already are several messages printed in NMI context: WARN_ON(in_nmi()), BUG_ON(in_nmi()), anything being printed out from MCE handlers. These are not easy to avoid. This patch reuses most of the code and makes it generic. It is useful for all messages and architectures that support NMI. The alternative printk_func is set when entering and is reseted when leaving NMI context. It queues IRQ work to copy the messages into the main ring buffer in a safe context. __printk_nmi_flush() copies all available messages and reset the buffer. Then we could use a simple cmpxchg operations to get synchronized with writers. There is also used a spinlock to get synchronized with other flushers. We do not longer use seq_buf because it depends on external lock. It would be hard to make all supported operations safe for a lockless use. It would be confusing and error prone to make only some operations safe. The code is put into separate printk/nmi.c as suggested by Steven Rostedt. It needs a per-CPU buffer and is compiled only on architectures that call nmi_enter(). This is achieved by the new HAVE_NMI Kconfig flag. The are MN10300 and Xtensa architectures. We need to clean up NMI handling there first. Let's do it separately. The patch is heavily based on the draft from Peter Zijlstra, see https://lkml.org/lkml/2015/6/10/327 [arnd@arndb.de: printk-nmi: use %zu format string for size_t] [akpm@linux-foundation.org: min_t->min - all types are size_t here] Signed-off-by: Petr Mladek <pmladek@suse.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Cc: Jan Kara <jack@suse.cz> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> [arm part] Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jiri Kosina <jkosina@suse.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: David Miller <davem@davemloft.net> Cc: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'x86-platform-for-linus' of ↵Linus Torvalds2016-05-16
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 platform updates from Ingo Molnar: "The main change is the addition of SGI/UV4 support" * 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) x86/platform/UV: Fix incorrect nodes and pnodes for cpuless and memoryless nodes x86/platform/UV: Remove Obsolete GRU MMR address translation x86/platform/UV: Update physical address conversions for UV4 x86/platform/UV: Build GAM reference tables x86/platform/UV: Support UV4 socket address changes x86/platform/UV: Add obtaining GAM Range Table from UV BIOS x86/platform/UV: Add UV4 addressing discovery function x86/platform/UV: Fold blade info into per node hub info structs x86/platform/UV: Allocate common per node hub info structs on local node x86/platform/UV: Move blade local processor ID to the per cpu info struct x86/platform/UV: Move scir info to the per cpu info struct x86/platform/UV: Create per cpu info structs to replace per hub info structs x86/platform/UV: Update MMIOH setup function to work for both UV3 and UV4 x86/platform/UV: Clean up redunduncies after merge of UV4 MMR definitions x86/platform/UV: Add UV4 Specific MMR definitions x86/platform/UV: Prep for UV4 MMR updates x86/platform/UV: Add UV MMR Illegal Access Function x86/platform/UV: Add UV4 Specific Defines x86/platform/UV: Add UV Architecture Defines x86/platform/UV: Add Initial UV4 definitions ...
| * Merge branch 'x86/urgent' into x86/platform, to resolve conflictIngo Molnar2016-05-05
| |\ | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/kernel/apic/x2apic_uv_x.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Fix incorrect nodes and pnodes for cpuless and memoryless nodesDimitri Sivanich2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes the problem of incorrect nodes and pnodes being returned when referring to nodes that either have no cpus (AKA "headless") or no memory. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Dimitri Sivanich <sivanich@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215406.192644884@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Update physical address conversions for UV4Mike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch builds support for the new conversions of physical addresses to and from sockets, pnodes and nodes in UV4. It is designed to be as efficient as possible as lookups are done inside an interrupt context in some cases. It will be further optimized when physical hardware is available to measure execution time. Tested-by: Dimitri Sivanich <sivanich@sgi.com> Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215405.841051741@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Build GAM reference tablesMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An aspect of the UV4 system architecture changes involve changing the way sockets, nodes, and pnodes are translated between one another. Decode the information from the BIOS provided EFI system table to build the needed conversion tables. Tested-by: Dimitri Sivanich <sivanich@sgi.com> Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215405.673495324@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Support UV4 socket address changesMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the UV4 system architecture addressing changes, BIOS now provides this information via an EFI system table. This is the initial decoding of that system table. It also collects the sizing information for later allocation of dynamic conversion tables. Tested-by: Dimitri Sivanich <sivanich@sgi.com> Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215405.503022681@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Add UV4 addressing discovery functionMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | UV4 requires early system wide addressing values. This involves the use of the CPUID instruction to obtain these values. The current function (detect_extended_topology()) in the kernel has been copied and streamlined, with the limitation that only CPU's used by UV architectures are supported. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215405.155660884@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Fold blade info into per node hub info structsMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Migrate references from the blade info structs to the per node hub info structs. This phases out the allocation of the list of per blade info structs on node 0, in favor of a per node hub info struct allocated on the node's local memory. There are also some minor cosemetic changes in the comments and whitespace to clean things up a bit. Tested-by: Dimitri Sivanich <sivanich@sgi.com> Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215404.987204515@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Allocate common per node hub info structs on local nodeMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allocate and setup per node hub info structs. CPU 0/Node 0 hub info is statically allocated to be accessible early in system startup. The remaining hub info structs are allocated on the node's local memory, and shared among the CPU's on that node. This leaves the small amount of info unique to each CPU in the per CPU info struct. Memory is saved by combining the common per node info fields to common node local structs. In addtion, since the info is read only only after setup, it should stay in the L3 cache of the local processor socket. This should therefore improve the cache hit rate when a group of cpus on a node are all interrupted for a common task. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Reviewed-by: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215404.813051625@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Move blade local processor ID to the per cpu info structMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move references to blade local processor ID to the new per cpu info structs. Create an access function that makes this move, and other potential moves opaque to callers of this function. Define a flag that indicates to callers in external GPL modules that this function replaces any local definition. This allows calling source code to be built for both pre-UV4 kernels as well as post-UV4 kernels. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215404.644173122@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Move scir info to the per cpu info structMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change the references to the SCIR fields to the new per cpu info structs. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215404.452538234@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Create per cpu info structs to replace per hub info structsMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The major portion of the hub info is common to all cpus on that hub. This is step one of moving the per cpu hub info to a per node hub info struct. This patch creates the small per cpu info struct that will contain only information specific to each CPU. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215404.282265563@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Update MMIOH setup function to work for both UV3 and UV4Mike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since UV3 and UV4 MMIOH regions are setup the same, we can use a common function to setup both. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215404.100504077@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Clean up redunduncies after merge of UV4 MMR definitionsMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clean up any redundancies caused by new UV4 MMR definitions superseding any previously definitions local to functions. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Reviewed-by: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215403.934728974@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Prep for UV4 MMR updatesMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cleanup patch to rearrange code and modify some defines so the next patch, the new UV4 MMR definitions can be merged cleanly. * Clean up the M/N related address constants (M is # of address bits per blade, N is the # of blade selection bits per SSI/partition). * Fix the lookup of the alias overlay addresses and NMI definitions to allow for flexibility in newer UV architecture types. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215403.401604203@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Add UV MMR Illegal Access FunctionMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This new function is generated by the UV MMR generation script to identify MMR registers and fields that are not defined for a specific UV architecture. With this switch, the immediate panic can be replaced with a message and a bad return value allowing either hardware or the emulator to diagnose the problem. It allows functions common to some UV arches to use common defines that might not be fully defined for all arches, as long as they do not reference them on the unsupported arches. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215403.231926687@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/platform/UV: Add UV4 Specific DefinesMike Travis2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add UV4 specific defines to determine if current system type is a UV4 system. Tested-by: John Estabrook <estabrook@sgi.com> Tested-by: Gary Kroening <gfk@sgi.com> Tested-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160429215403.072323684@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2016-05-16
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "The main changes in this cycle were: - MSR access API fixes and enhancements (Andy Lutomirski) - early exception handling improvements (Andy Lutomirski) - user-space FS/GS prctl usage fixes and improvements (Andy Lutomirski) - Remove the cpu_has_*() APIs and replace them with equivalents (Borislav Petkov) - task switch micro-optimization (Brian Gerst) - 32-bit entry code simplification (Denys Vlasenko) - enhance PAT handling in enumated CPUs (Toshi Kani) ... and lots of other cleanups/fixlets" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits) x86/arch_prctl/64: Restore accidentally removed put_cpu() in ARCH_SET_GS x86/entry/32: Remove asmlinkage_protect() x86/entry/32: Remove GET_THREAD_INFO() from entry code x86/entry, sched/x86: Don't save/restore EFLAGS on task switch x86/asm/entry/32: Simplify pushes of zeroed pt_regs->REGs selftests/x86/ldt_gdt: Test set_thread_area() deletion of an active segment x86/tls: Synchronize segment registers in set_thread_area() x86/asm/64: Rename thread_struct's fs and gs to fsbase and gsbase x86/arch_prctl/64: Remove FSBASE/GSBASE < 4G optimization x86/segments/64: When load_gs_index fails, clear the base x86/segments/64: When loadsegment(fs, ...) fails, clear the base x86/asm: Make asm/alternative.h safe from assembly x86/asm: Stop depending on ptrace.h in alternative.h x86/entry: Rename is_{ia32,x32}_task() to in_{ia32,x32}_syscall() x86/asm: Make sure verify_cpu() has a good stack x86/extable: Add a comment about early exception handlers x86/msr: Set the return value to zero when native_rdmsr_safe() fails x86/paravirt: Make "unsafe" MSR accesses unsafe even if PARAVIRT=y x86/paravirt: Add paravirt_{read,write}_msr() x86/msr: Carry on after a non-"safe" MSR access fails ...
| * | Merge branch 'x86/urgent' into x86/asm, to refresh the treeIngo Molnar2016-04-29
| |\| | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/cpufeature: Replace cpu_has_apic with boot_cpu_has() usageBorislav Petkov2016-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: iommu@lists.linux-foundation.org Cc: linux-pm@vger.kernel.org Cc: oprofile-list@lists.sf.net Link: http://lkml.kernel.org/r/1459801503-15600-8-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/cpufeature: Replace cpu_has_tsc with boot_cpu_has() usageBorislav Petkov2016-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Sailer <t.sailer@alumni.ethz.ch> Link: http://lkml.kernel.org/r/1459801503-15600-7-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/cpufeature: Remove cpu_has_x2apicBorislav Petkov2016-03-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Tony Luck <tony.luck@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1459266123-21878-5-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | x86/platform/UV: Bring back the call to map_low_mmrs in uv_system_initAlex Thorlton2016-05-05
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A while back the following commit: d394f2d9d8e1 ("x86/platform/UV: Remove EFI memmap quirk for UV2+") changed uv_system_init() to only call map_low_mmrs() on older UV1 hardware, which requires EFI_OLD_MEMMAP to be set in order to boot. The recent changes to the EFI memory mapping code in: d2f7cbe7b26a ("x86/efi: Runtime services virtual mapping") exposed some issues with the fact that we were relying on the EFI memory mapping mechanisms to map in our MMRs for us, after commit d394f2d9d8e1. Rather than revert the entire commit and go back to forcing EFI_OLD_MEMMAP on all UVs, we're going to add the call to map_low_mmrs() back into uv_system_init(), and then fix up our EFI runtime calls to use the appropriate page table. For now, UV2+ will still need efi=old_map to boot, but there will be other changes soon that should eliminate the need for this. Signed-off-by: Alex Thorlton <athorlton@sgi.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Adam Buchbinder <adam.buchbinder@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Russ Anderson <rja@sgi.com> Cc: Dimitri Sivanich <sivanich@sgi.com> Link: http://lkml.kernel.org/r/1462401592-120735-1-git-send-email-athorlton@sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/apic: Handle zero vector gracefully in clear_vector_irq()Keith Busch2016-04-28
|/ | | | | | | | | | | | | | | | | | | | | If x86_vector_alloc_irq() fails x86_vector_free_irqs() is invoked to cleanup the already allocated vectors. This subsequently calls clear_vector_irq(). The failed irq has no vector assigned, which triggers the BUG_ON(!vector) in clear_vector_irq(). We cannot suppress the call to x86_vector_free_irqs() for the failed interrupt, because the other data related to this irq must be cleaned up as well. So calling clear_vector_irq() with vector == 0 is legitimate. Remove the BUG_ON and return if vector is zero, [ tglx: Massaged changelog ] Fixes: b5dc8e6c21e7 "x86/irq: Use hierarchical irqdomain to manage CPU interrupt vectors" Signed-off-by: Keith Busch <keith.busch@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2016-03-24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes: - fix hotplug bugs - fix irq live lock - fix various topology handling bugs - fix APIC ACK ordering - fix PV iopl handling - fix speling - fix/tweak memcpy_mcsafe() return value - fix fbcon bug - remove stray prototypes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/msr: Remove unused native_read_tscp() x86/apic: Remove declaration of unused hw_nmi_is_cpu_stuck x86/oprofile/nmi: Add missing hotplug FROZEN handling x86/hpet: Use proper mask to modify hotplug action x86/apic/uv: Fix the hotplug notifier x86/apb/timer: Use proper mask to modify hotplug action x86/topology: Use total_cpus not nr_cpu_ids for logical packages x86/topology: Fix Intel HT disable x86/topology: Fix logical package mapping x86/irq: Cure live lock in fixup_irqs() x86/tsc: Prevent NULL pointer deref in calibrate_delay_is_known() x86/apic: Fix suspicious RCU usage in smp_trace_call_function_interrupt() x86/iopl: Fix iopl capability check on Xen PV x86/iopl/64: Properly context-switch IOPL on Xen PV selftests/x86: Add an iopl test x86/mm, x86/mce: Fix return type/value for memcpy_mcsafe() x86/video: Don't assume all FB devices are PCI devices arch/x86/irq: Purge useless handler declarations from hw_irq.h x86: Fix misspellings in comments
| * x86/apic/uv: Fix the hotplug notifierThomas Gleixner2016-03-19
| | | | | | | | | | | | | | | | | | | | | | The notifier is missing the CPU_DOWN_FAILED transition. That leaves the heartbeat disabled when CPU_DOWN_PREPARE fails. It also does not handle the FROZEN transition variants. That might not be an issue for UV, but it's inconsistent. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Dimitri Sivanich <sivanich@sgi.com>
| * x86/irq: Cure live lock in fixup_irqs()Thomas Gleixner2016-03-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Harry reported, that he's able to trigger a system freeze with cpu hot unplug. The freeze turned out to be a live lock caused by recent changes in irq_force_complete_move(). When fixup_irqs() and from there irq_force_complete_move() is called on the dying cpu, then all other cpus are in stop machine an wait for the dying cpu to complete the teardown. If there is a move of an interrupt pending then irq_force_complete_move() sends the cleanup IPI to the cpus in the old_domain mask and waits for them to clear the mask. That's obviously impossible as those cpus are firmly stuck in stop machine with interrupts disabled. I should have known that, but I completely overlooked it being concentrated on the locking issues around the vectors. And the existance of the call to __irq_complete_move() in the code, which actually sends the cleanup IPI made it reasonable to wait for that cleanup to complete. That call was bogus even before the recent changes as it was just a pointless distraction. We have to look at two cases: 1) The move_in_progress flag of the interrupt is set This means the ioapic has been updated with the new vector, but it has not fired yet. In theory there is a race: set_ioapic(new_vector) <-- Interrupt is raised before update is effective, i.e. it's raised on the old vector. So if the target cpu cannot handle that interrupt before the old vector is cleaned up, we get a spurious interrupt and in the worst case the ioapic irq line becomes stale, but my experiments so far have only resulted in spurious interrupts. But in case of cpu hotplug this should be a non issue because if the affinity update happens right before all cpus rendevouz in stop machine, there is no way that the interrupt can be blocked on the target cpu because all cpus loops first with interrupts enabled in stop machine, so the old vector is not yet cleaned up when the interrupt fires. So the only way to run into this issue is if the delivery of the interrupt on the apic/system bus would be delayed beyond the point where the target cpu disables interrupts in stop machine. I doubt that it can happen, but at least there is a theroretical chance. Virtualization might be able to expose this, but AFAICT the IOAPIC emulation is not as stupid as the real hardware. I've spent quite some time over the weekend to enforce that situation, though I was not able to trigger the delayed case. 2) The move_in_progress flag is not set and the old_domain cpu mask is not empty. That means, that an interrupt was delivered after the change and the cleanup IPI has been sent to the cpus in old_domain, but not all CPUs have responded to it yet. In both cases we can assume that the next interrupt will arrive on the new vector, so we can cleanup the old vectors on the cpus in the old_domain cpu mask. Fixes: 98229aa36caa "x86/irq: Plug vector cleanup race" Reported-by: Harry Junior <harryjr@outlook.fr> Tested-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Joe Lawrence <joe.lawrence@stratus.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1603140931430.3657@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * Merge branch 'x86/cleanups' into x86/urgentIngo Molnar2016-03-17
| |\ | | | | | | | | | | | | | | | Pull in some merge window leftovers. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * x86: Fix misspellings in commentsAdam Buchbinder2016-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: trivial@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | kernel: add kcov code coverageDmitry Vyukov2016-03-22
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kcov provides code coverage collection for coverage-guided fuzzing (randomized testing). Coverage-guided fuzzing is a testing technique that uses coverage feedback to determine new interesting inputs to a system. A notable user-space example is AFL (http://lcamtuf.coredump.cx/afl/). However, this technique is not widely used for kernel testing due to missing compiler and kernel support. kcov does not aim to collect as much coverage as possible. It aims to collect more or less stable coverage that is function of syscall inputs. To achieve this goal it does not collect coverage in soft/hard interrupts and instrumentation of some inherently non-deterministic or non-interesting parts of kernel is disbled (e.g. scheduler, locking). Currently there is a single coverage collection mode (tracing), but the API anticipates additional collection modes. Initially I also implemented a second mode which exposes coverage in a fixed-size hash table of counters (what Quentin used in his original patch). I've dropped the second mode for simplicity. This patch adds the necessary support on kernel side. The complimentary compiler support was added in gcc revision 231296. We've used this support to build syzkaller system call fuzzer, which has found 90 kernel bugs in just 2 months: https://github.com/google/syzkaller/wiki/Found-Bugs We've also found 30+ bugs in our internal systems with syzkaller. Another (yet unexplored) direction where kcov coverage would greatly help is more traditional "blob mutation". For example, mounting a random blob as a filesystem, or receiving a random blob over wire. Why not gcov. Typical fuzzing loop looks as follows: (1) reset coverage, (2) execute a bit of code, (3) collect coverage, repeat. A typical coverage can be just a dozen of basic blocks (e.g. an invalid input). In such context gcov becomes prohibitively expensive as reset/collect coverage steps depend on total number of basic blocks/edges in program (in case of kernel it is about 2M). Cost of kcov depends only on number of executed basic blocks/edges. On top of that, kernel requires per-thread coverage because there are always background threads and unrelated processes that also produce coverage. With inlined gcov instrumentation per-thread coverage is not possible. kcov exposes kernel PCs and control flow to user-space which is insecure. But debugfs should not be mapped as user accessible. Based on a patch by Quentin Casasnovas. [akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode'] [akpm@linux-foundation.org: unbreak allmodconfig] [akpm@linux-foundation.org: follow x86 Makefile layout standards] Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: syzkaller <syzkaller@googlegroups.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Tavis Ormandy <taviso@google.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Kees Cook <keescook@google.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: David Drysdale <drysdale@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'irq-core-for-linus' of ↵Linus Torvalds2016-03-15
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "The 4.6 pile of irq updates contains: - Support for IPI irqdomains to support proper integration of IPIs to and from coprocessors. The first user of this new facility is MIPS. The relevant MIPS patches come with the core to avoid merge ordering issues and have been acked by Ralf. - A new command line option to set the default interrupt affinity mask at boot time. - Support for some more new ARM and MIPS interrupt controllers: tango, alpine-msix and bcm6345-l1 - Two small cleanups for x86/apic which we merged into irq/core to avoid yet another branch in x86 with two tiny commits. - The usual set of updates, cleanups in drivers/irqchip. Mostly in the area of ARM-GIC, arada-37-xp and atmel chips. Nothing outstanding here" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits) irqchip/irq-alpine-msi: Release the correct domain on error irqchip/mxs: Fix error check of of_io_request_and_map() irqchip/sunxi-nmi: Fix error check of of_io_request_and_map() genirq: Export IRQ functions for module use irqchip/gic/realview: Support more RealView DCC variants Documentation/bindings: Document the Alpine MSIX driver irqchip: Add the Alpine MSIX interrupt controller irqchip/gic-v3: Always return IRQ_SET_MASK_OK_DONE in gic_set_affinity irqchip/gic-v3-its: Mark its_init() and its children as __init irqchip/gic-v3: Remove gic_root_node variable from the ITS code irqchip/gic-v3: ACPI: Add redistributor support via GICC structures irqchip/gic-v3: Add ACPI support for GICv3/4 initialization irqchip/gic-v3: Refactor gic_of_init() for GICv3 driver x86/apic: Deinline _flat_send_IPI_mask, save ~150 bytes x86/apic: Deinline __default_send_IPI_*, save ~200 bytes dt-bindings: interrupt-controller: Add SoC-specific compatible string to Marvell ODMI irqchip/mips-gic: Add new DT property to reserve IPIs MIPS: Delete smp-gic.c MIPS: Make smp CMP, CPS and MT use the new generic IPI functions MIPS: Add generic SMP IPI support ...
| * | x86/apic: Deinline _flat_send_IPI_mask, save ~150 bytesDenys Vlasenko2016-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | _flat_send_IPI_mask: 157 bytes, 3 callsites text data bss dec hex filename 96183823 20860520 36122624 153166967 9212477 vmlinux1_before 96183699 20860520 36122624 153166843 92123fb vmlinux Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Borislav Petkov <bp@alien.de> Cc: Daniel J Blueman <daniel@numascale.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Travis <travis@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1457287876-6001-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/apic: Deinline __default_send_IPI_*, save ~200 bytesDenys Vlasenko2016-03-08
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __default_send_IPI_shortcut: 49 bytes, 2 callsites __default_send_IPI_dest_field: 108 bytes, 7 callsites text data bss dec hex filename 96184086 20860488 36122624 153167198 921255e vmlinux_before 96183823 20860520 36122624 153166967 9212477 vmlinux Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Borislav Petkov <bp@alien.de> Cc: Daniel J Blueman <daniel@numascale.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Travis <travis@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1457287876-6001-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2016-03-15
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "This is another big update. Main changes are: - lots of x86 system call (and other traps/exceptions) entry code enhancements. In particular the complex parts of the 64-bit entry code have been migrated to C code as well, and a number of dusty corners have been refreshed. (Andy Lutomirski) - vDSO special mapping robustification and general cleanups (Andy Lutomirski) - cpufeature refactoring, cleanups and speedups (Borislav Petkov) - lots of other changes ..." * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits) x86/cpufeature: Enable new AVX-512 features x86/entry/traps: Show unhandled signal for i386 in do_trap() x86/entry: Call enter_from_user_mode() with IRQs off x86/entry/32: Change INT80 to be an interrupt gate x86/entry: Improve system call entry comments x86/entry: Remove TIF_SINGLESTEP entry work x86/entry/32: Add and check a stack canary for the SYSENTER stack x86/entry/32: Simplify and fix up the SYSENTER stack #DB/NMI fixup x86/entry: Only allocate space for tss_struct::SYSENTER_stack if needed x86/entry: Vastly simplify SYSENTER TF (single-step) handling x86/entry/traps: Clear DR6 early in do_debug() and improve the comment x86/entry/traps: Clear TIF_BLOCKSTEP on all debug exceptions x86/entry/32: Restore FLAGS on SYSEXIT x86/entry/32: Filter NT and speed up AC filtering in SYSENTER x86/entry/compat: In SYSENTER, sink AC clearing below the existing FLAGS test selftests/x86: In syscall_nt, test NT|TF as well x86/asm-offsets: Remove PARAVIRT_enabled x86/entry/32: Introduce and use X86_BUG_ESPFIX instead of paravirt_enabled uprobes: __create_xol_area() must nullify xol_mapping.fault x86/cpufeature: Create a new synthetic cpu capability for machine check recovery ...
| * | Merge branch 'x86/urgent' into x86/asm, to pick up fixesIngo Molnar2016-02-18
| |\| | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/cpufeature: Replace the old static_cpu_has() with safe variantBorislav Petkov2016-01-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So the old one didn't work properly before alternatives had run. And it was supposed to provide an optimized JMP because the assumption was that the offset it is jumping to is within a signed byte and thus a two-byte JMP. So I did an x86_64 allyesconfig build and dumped all possible sites where static_cpu_has() was used. The optimization amounted to all in all 12(!) places where static_cpu_has() had generated a 2-byte JMP. Which has saved us a whopping 36 bytes! This clearly is not worth the trouble so we can remove it. The only place where the optimization might count - in __switch_to() - we will handle differently. But that's not subject of this patch. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-6-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | x86/topology: Create logical package idThomas Gleixner2016-02-29
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For per package oriented services we must be able to rely on the number of CPU packages to be within bounds. Create a tracking facility, which - calculates the number of possible packages depending on nr_cpu_ids after boot - makes sure that the package id is within the number of possible packages. If the apic id is outside we map it to a logical package id if there is enough space available. Provide interfaces for drivers to query the mapping and do translations from physcial to logical ids. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Harish Chegondi <harish.chegondi@intel.com> Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/20160222221011.541071755@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/platform/UV: Remove EFI memmap quirk for UV2+Alex Thorlton2016-01-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit a5d90c923bcf ("x86/efi: Quirk out SGI UV") added a quirk to efi_apply_memmap_quirks to force SGI UV systems to fall back to the old EFI memmap mechanism. We have a BIOS fix for this issue on all systems except for UV1. This commit fixes up the EFI quirk/MMR mapping code so that we only apply the special case to UV1 hardware. Signed-off-by: Alex Thorlton <athorlton@sgi.com> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Dimitri Sivanich <sivanich@sgi.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hedi Berriche <hedi@sgi.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Travis <travis@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1449867585-189233-2-git-send-email-athorlton@sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/irq: Plug vector cleanup raceThomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We still can end up with a stale vector due to the following: CPU0 CPU1 CPU2 lock_vector() data->move_in_progress=0 sendIPI() unlock_vector() set_affinity() assign_irq_vector() lock_vector() handle_IPI move_in_progress = 1 lock_vector() unlock_vector() move_in_progress == 1 So we need to serialize the vector assignment against a pending cleanup. The solution is rather simple now. We not only check for the move_in_progress flag in assign_irq_vector(), we also check whether there is still a cleanup pending in the old_domain cpumask. If so, we return -EBUSY to the caller and let him deal with it. Though we have to be careful in the cpu unplug case. If the cleanout has not yet completed then the following setaffinity() call would return -EBUSY. Add code which prevents this. Full context is here: http://lkml.kernel.org/r/5653B688.4050809@stratus.com Reported-and-tested-by: Joe Lawrence <joe.lawrence@stratus.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160107.207265407@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/irq: Call irq_force_move_complete with irq descriptorThomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | First of all there is no point in looking up the irq descriptor again, but we also need the descriptor for the final cleanup race fix in the next patch. Make that change seperate. No functional difference. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160107.125211743@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/irq: Remove outgoing CPU from vector cleanup maskThomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We want to synchronize new vector assignments with a pending cleanup. Remove a dying cpu from a pending cleanup mask. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160107.045961667@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/irq: Remove the cpumask allocation from send_cleanup_vector()Thomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no need to allocate a new cpumask for sending the cleanup vector. The old_domain mask is now protected by the vector_lock, so we can safely remove the offline cpus from it and send the IPI with the resulting mask. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160106.967993932@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/irq: Clear move_in_progress before sending cleanup IPIThomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | send_cleanup_vector() fiddles with the old_domain mask unprotected because it relies on the protection by the move_in_progress flag. But this is fatal, as the flag is reset after the IPI has been sent. So a cpu which receives the IPI can still see the flag set and therefor ignores the cleanup request. If no other cleanup request happens then the vector stays stale on that cpu and in case of an irq removal the vector still persists. That can lead to use after free when the next cleanup IPI happens. Protect the code with vector_lock and clear move_in_progress before sending the IPI. This does not plug the race which Joe reported because: CPU0 CPU1 CPU2 lock_vector() data->move_in_progress=0 sendIPI() unlock_vector() set_affinity() assign_irq_vector() lock_vector() handle_IPI move_in_progress = 1 lock_vector() unlock_vector() move_in_progress == 1 The full fix comes with a later patch. Reported-and-tested-by: Joe Lawrence <joe.lawrence@stratus.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160106.892412198@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/irq: Remove offline cpus from vector cleanupThomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No point of keeping offline cpus in the cleanup mask. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160106.808642683@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/irq: Get rid of code duplicationThomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reusing an existing vector and assigning a new vector has duplicated code. Consolidate it. This is also a preparatory patch for finally plugging the cleanup race. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160106.721599216@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/irq: Copy vectormask instead of an AND operationThomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the case that the new vector mask is a subset of the existing mask there is no point to do a AND operation of currentmask & newmask. The result is newmask. So we can simply copy the new mask to the current mask and be done with it. Preparatory patch for further consolidation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160106.640253454@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/irq: Check vector allocation earlyThomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __assign_irq_vector() uses the vector_cpumask which is assigned by apic->vector_allocation_domain() without doing basic sanity checks. That can result in a situation where the final assignement of a newly found vector fails in apic->cpu_mask_to_apicid_and(). So we have to do rollbacks for no reason. apic->cpu_mask_to_apicid_and() only fails if vector_cpumask & requested_cpumask & cpu_online_mask is empty. Check for this condition right away and if the result is empty try immediately the next possible cpu in the requested mask. So in case of a failure the old setting is unchanged and we can remove the rollback code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160106.561877324@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/irq: Reorganize the search in assign_irq_vectorThomas Gleixner2016-01-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Split out the code which advances the target cpu for the search so we can reuse it for the next patch which adds an early validation check for the vectormask which we get from the apic. Add comments while at it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Jeremiah Mahler <jmmahler@gmail.com> Cc: andy.shevchenko@gmail.com Cc: Guenter Roeck <linux@roeck-us.net> Cc: stable@vger.kernel.org #4.3+ Link: http://lkml.kernel.org/r/20151231160106.484562040@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>