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* x86/apic: Use u32 for [gs]et_apic_id()Thomas Gleixner2023-10-101-2/+2
| | | | | | | | | | | | | | | | | | APIC IDs are used with random data types u16, u32, int, unsigned int, unsigned long. Make it all consistently use u32 because that reflects the hardware register width. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085113.172569282@linutronix.de
* x86/apic: Use u32 for phys_pkg_id()Thomas Gleixner2023-10-101-1/+1
| | | | | | | | | | | | | | | | | | | APIC IDs are used with random data types u16, u32, int, unsigned int, unsigned long. Make it all consistently use u32 because that reflects the hardware register width even if that callback going to be removed soonish. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085113.113097126@linutronix.de
* x86/apic: Use u32 for cpu_present_to_apicid()Thomas Gleixner2023-10-101-1/+1
| | | | | | | | | | | | | | | | | | | APIC IDs are used with random data types u16, u32, int, unsigned int, unsigned long. Make it all consistently use u32 because that reflects the hardware register width and fixup a few related usage sites for consistency sake. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085113.054064391@linutronix.de
* x86/cpu: Encapsulate topology information in cpuinfo_x86Thomas Gleixner2023-10-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | The topology related information is randomly scattered across cpuinfo_x86. Create a new structure cpuinfo_topo and move in a first step initial_apicid and apicid into it. Aside of being better readable this is in preparation for replacing the horribly fragile CPU topology evaluation code further down the road. Consolidate APIC ID fields to u32 as that represents the hardware type. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085112.269787744@linutronix.de
* x86/xen/apic: Mark apic __ro_after_initThomas Gleixner2023-08-091-15/+13
| | | | | | | | | | | | | | | | | Nothing can change it post init. Remove the 32bit callbacks and comments as XENPV is strictly 64bit. While at it mop up the whitespace damage which causes eyebleed due to an editor which is highlighting it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest) Cc: Juergen Gross <jgross@suse.com>
* x86/xen/apic: Use standard apic driver mechanism for Xen PVJuergen Gross2023-08-091-11/+0
| | | | | | | | | | | | | | | | | | | Instead of setting the Xen PV apic driver very early during boot, just use the standard apic driver probing by setting an appropriate x86_init.irqs.intr_mode_init callback. At the same time eliminate xen_apic_check() which has never been used. The #ifdef CONFIG_X86_LOCAL_APIC around the call of xen_init_apic() can be removed, too, as CONFIG_XEN depends on CONFIG_X86_LOCAL_APIC. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest) Link: https://lore.kernel.org/lkml/aa086365-fd02-210f-67c6-5c9175c0dfee@suse.com
* x86/apic: Provide common init infrastructureThomas Gleixner2023-08-091-7/+3
| | | | | | | | | | | | | | | | In preparation for converting the hotpath APIC callbacks to static keys, provide common initialization infrastructure. Lift apic_install_drivers() from probe_64.c and convert all places which switch the apic instance by storing the pointer to use apic_install_driver() as a first step. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Remove pointless arguments from [native_]eoi_write()Thomas Gleixner2023-08-091-1/+6
| | | | | | | | | | | | | | | Every callsite hands in the same constants which is a pointless exercise and cannot be optimized by the compiler due to the indirect calls. Use the constants in the eoi() callbacks and remove the arguments. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Wei Liu <wei.liu@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Sanitize APIC ID range validationThomas Gleixner2023-08-091-6/+0
| | | | | | | | | | | | | | | Now that everything has apic::max_apic_id set and the eventual update for the x2APIC case is in place, switch the apic_id_valid() helper to use apic::max_apic_id and remove the apic::apic_id_valid() callback. [ dhansen: Fix subject typo ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Add max_apic_id memberThomas Gleixner2023-08-091-0/+1
| | | | | | | | | | | | | | | | There is really no point to have a callback which compares numbers. Add a field which allows each APIC to store the maximum APIC ID supported and fill it in for all APIC incarnations. The next step will remove the callback. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Allow apic::safe_wait_icr_idle() to be NULLThomas Gleixner2023-08-091-6/+0
| | | | | | | | | | | | | | Remove tons of NOOP callbacks by making the invocation of safe_wait_icr_idle() conditional in the inline wrapper. Will be replaced by a static_call_cond() later. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Allow apic::wait_icr_idle() to be NULLThomas Gleixner2023-08-091-5/+0
| | | | | | | | | | | | Nuke more NOOP callbacks and make the invocation conditional. Will be replaced with a static call later. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Mop up apic::apic_id_registered()Thomas Gleixner2023-08-091-6/+0
| | | | | | | | | | | | | Really not a hotpath and again no reason for having a gazillion of empty callbacks returning 1. Make it return bool and provide one shared implementation for the remaining users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Mop up *setup_apic_routing()Thomas Gleixner2023-08-091-1/+0
| | | | | | | | | | | | | | | | default_setup_apic_routing() is a complete misnomer. On 64bit it does the actual APIC probing and on 32bit it is used to force select the bigsmp APIC and to emit a redundant message in the apic::setup_apic_routing() callback. Rename the 64bit and 32bit function so they reflect what they are doing and remove the useless APIC callback. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Nuke apic::apicid_to_cpu_present()Thomas Gleixner2023-08-091-1/+0
| | | | | | | | | | | | | | | This is only used on 32bit and is a wrapper around physid_set_mask_of_physid() in all 32bit APIC drivers. Remove the callback and use physid_set_mask_of_physid() in the code directly, Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Nuke empty init_apic_ldr() callbacksThomas Gleixner2023-08-091-1/+0
| | | | | | | | | | | | | | | | | | | | apic::init_apic_ldr() is only invoked when the APIC is initialized. So there is really no point in having: - Default empty callbacks all over the place - Two implementations of the actual LDR init function where one is just unreadable gunk but does exactly the same as the other. Make the apic::init_apic_ldr() invocation conditional, remove the empty callbacks and consolidate the two implementation into one. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Remove check_phys_apicid_present()Thomas Gleixner2023-08-091-1/+0
| | | | | | | | | | | | The only silly usage site is gone. Remove the gunk which was even outright wrong in the bigsmp_32 case which returned true unconditionally. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* x86/apic: Nuke unused apic::inquire_remote_apic()Thomas Gleixner2023-08-091-7/+0
| | | | | | | | | | | Put it to the other historical leftovers. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
* arch:x86:xen: Remove unnecessary assignment in xen_apic_read()jianchunfu2022-03-151-1/+1
| | | | | | | | | | | In the function xen_apic_read(), the initialized value of 'ret' is unused because it will be assigned by the function HYPERVISOR_platform_op(), thus remove it. Signed-off-by: jianchunfu <jianchunfu@cmss.chinamobile.com> Link: https://lore.kernel.org/r/20220314070514.2602-1-jianchunfu@cmss.chinamobile.com Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
* x86/apic: Cleanup destination modeThomas Gleixner2020-10-281-2/+1
| | | | | | | | | | | | | apic::irq_dest_mode is actually a boolean, but defined as u32 and named in a way which does not explain what it means. Make it a boolean and rename it to 'dest_mode_logical' Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-9-dwmw2@infradead.org
* x86/apic: Get rid of apic:: Dest_logicalThomas Gleixner2020-10-281-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | struct apic has two members which store information about the destination mode: dest_logical and irq_dest_mode. dest_logical contains a mask which was historically used to set the destination mode in IPI messages. Over time the usage was reduced and the logical/physical functions were seperated. There are only a few places which still use 'dest_logical' but they can use 'irq_dest_mode' instead. irq_dest_mode is actually a boolean where 0 means physical destination mode and 1 means logical destination mode. Of course the name does not reflect the functionality. This will be cleaned up in a subsequent change. Remove apic::dest_logical and fixup the remaining users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201024213535.443185-8-dwmw2@infradead.org
* Merge tag 'for-linus-5.9-rc1b-tag' of ↵Linus Torvalds2020-08-141-17/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull more xen updates from Juergen Gross: - Remove support for running as 32-bit Xen PV-guest. 32-bit PV guests are rarely used, are lacking security fixes for Meltdown, and can be easily replaced by PVH mode. Another series for doing more cleanup will follow soon (removal of 32-bit-only pvops functionality). - Fixes and additional features for the Xen display frontend driver. * tag 'for-linus-5.9-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: drm/xen-front: Pass dumb buffer data offset to the backend xen: Sync up with the canonical protocol definition in Xen drm/xen-front: Add YUYV to supported formats drm/xen-front: Fix misused IS_ERR_OR_NULL checks xen/gntdev: Fix dmabuf import with non-zero sgt offset x86/xen: drop tests for highmem in pv code x86/xen: eliminate xen-asm_64.S x86/xen: remove 32-bit Xen PV guest support
| * x86/xen: remove 32-bit Xen PV guest supportJuergen Gross2020-08-111-17/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | Xen is requiring 64-bit machines today and since Xen 4.14 it can be built without 32-bit PV guest support. There is no need to carry the burden of 32-bit PV guest support in the kernel any longer, as new guests can be either HVM or PVH, or they can use a 64 bit kernel. Remove the 32-bit Xen PV support from the kernel. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
* | locking/seqlock, headers: Untangle the spaghetti monsterPeter Zijlstra2020-08-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By using lockdep_assert_*() from seqlock.h, the spaghetti monster attacked. Attack back by reducing seqlock.h dependencies from two key high level headers: - <linux/seqlock.h>: -Remove <linux/ww_mutex.h> - <linux/time.h>: -Remove <linux/seqlock.h> - <linux/sched.h>: +Add <linux/seqlock.h> The price was to add it to sched.h ... Core header fallout, we add direct header dependencies instead of gaining them parasitically from higher level headers: - <linux/dynamic_queue_limits.h>: +Add <asm/bug.h> - <linux/hrtimer.h>: +Add <linux/seqlock.h> - <linux/ktime.h>: +Add <asm/bug.h> - <linux/lockdep.h>: +Add <linux/smp.h> - <linux/sched.h>: +Add <linux/seqlock.h> - <linux/videodev2.h>: +Add <linux/kernel.h> Arch headers fallout: - PARISC: <asm/timex.h>: +Add <asm/special_insns.h> - SH: <asm/io.h>: +Add <asm/page.h> - SPARC: <asm/timer_64.h>: +Add <uapi/asm/asi.h> - SPARC: <asm/vvar.h>: +Add <asm/processor.h>, <asm/barrier.h> -Remove <linux/seqlock.h> - X86: <asm/fixmap.h>: +Add <asm/pgtable_types.h> -Remove <asm/acpi.h> There's also a bunch of parasitic header dependency fallout in .c files, not listed separately. [ mingo: Extended the changelog, split up & fixed the original patch. ] Co-developed-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200804133438.GK2674@hirez.programming.kicks-ass.net
* | x86/headers: Remove APIC headers from <asm/smp.h>Ingo Molnar2020-08-061-0/+1
|/ | | | | | | | | | | The APIC headers are relatively complex and bring in additional header dependencies - while smp.h is a relatively simple header included from high level headers. Remove the dependency and add in the missing #include's in .c files where they gained it indirectly before. Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'WIP.x86/asm' into x86/urgent, because the topic is readyIngo Molnar2018-04-121-1/+1
|\ | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86/apic: Rename variables and functions related to x86_io_apic_opsBaoquan He2018-02-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The names of x86_io_apic_ops and its two member variables are misleading: The ->read() member is to read IO_APIC reg, while ->disable() which is called by native_disable_io_apic()/irq_remapping_disable_io_apic() is actually used to restore boot IRQ mode, not to disable the IO-APIC. So rename x86_io_apic_ops to 'x86_apic_ops' since it doesn't only handle the IO-APIC, but also the local APIC. Also rename its member variables and the related callbacks. Signed-off-by: Baoquan He <bhe@redhat.com> Reviewed-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: douly.fnst@cn.fujitsu.com Cc: joro@8bytes.org Cc: prarit@redhat.com Cc: uobergfe@redhat.com Link: http://lkml.kernel.org/r/20180214054656.3780-6-bhe@redhat.com [ Rewrote the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/apic: Fix signedness bug in APIC ID validity checksLi RongQing2018-04-101-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | The APIC ID as parsed from ACPI MADT is validity checked with the apic->apic_id_valid() callback, which depends on the selected APIC type. For non X2APIC types APIC IDs >= 0xFF are invalid, but values > 0x7FFFFFFF are detected as valid. This happens because the 'apicid' argument of the apic_id_valid() callback is type 'int'. So the resulting comparison apicid < 0xFF evaluates to true for all unsigned int values > 0x7FFFFFFF which are handed to default_apic_id_valid(). As a consequence, invalid APIC IDs in !X2APIC mode are considered valid and accounted as possible CPUs. Change the apicid argument type of the apic_id_valid() callback to u32 so the evaluation is unsigned and returns the correct result. [ tglx: Massaged changelog ] Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Cc: jgross@suse.com Cc: Dou Liyang <douly.fnst@cn.fujitsu.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/1523322966-10296-1-git-send-email-lirongqing@baidu.com
* Merge tag 'for-linus-4.15-rc4-tag' of ↵Linus Torvalds2017-12-151-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: "Two minor fixes for running as Xen dom0: - when built as 32 bit kernel on large machines the Xen LAPIC emulation should report a rather modern LAPIC in order to support enough APIC-Ids - The Xen LAPIC emulation is needed for dom0 only, so build it only for kernels supporting to run as Xen dom0" * tag 'for-linus-4.15-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: XEN_ACPI_PROCESSOR is Dom0-only x86/Xen: don't report ancient LAPIC version
| * x86/Xen: don't report ancient LAPIC versionJan Beulich2017-12-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Unconditionally reporting a value seen on the P4 or older invokes functionality like io_apic_get_unique_id() on 32-bit builds, resulting in a panic() with sufficiently many CPUs and/or IO-APICs. Doing what that function does would be the hypervisor's responsibility anyway, so makes no sense to be used when running on Xen. Uniformly report a more modern version; this shouldn't matter much as both LAPIC and IO-APIC are being managed entirely / mostly by the hypervisor. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
* | Merge branch 'linus' into x86/apic, to resolve conflictsIngo Molnar2017-11-071-0/+1
|\ \ | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/include/asm/x2apic.h Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | x86/apic: Remove unused callbacksThomas Gleixner2017-09-251-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the old allocator is gone, these apic functions are unused. Remove them. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Yu Chen <yu.c.chen@intel.com> Acked-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rui Zhang <rui.zhang@intel.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Len Brown <lenb@kernel.org> Link: https://lkml.kernel.org/r/20170913213155.524662349@linutronix.de
* | x86/apic: Add replacement for cpu_mask_to_apicid()Thomas Gleixner2017-09-251-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As preparation for replacing the vector allocator, provide a new function which takes a cpu number instead of a cpu mask to calculate/lookup the resulting APIC destination id. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Yu Chen <yu.c.chen@intel.com> Acked-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rui Zhang <rui.zhang@intel.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Len Brown <lenb@kernel.org>
* | x86/apic: Get rid of apic->target_cpusThomas Gleixner2017-09-251-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The target_cpus() callback of the apic struct is not really useful. Some APICs return cpu_online_mask and others cpus_all_mask. The latter is bogus as it does not take holes in the cpus_possible_mask into account. Replace it with cpus_online_mask which makes the most sense and remove the callback. The usage sites will be removed in a later step anyway, so get rid of it now to have incremental changes. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Yu Chen <yu.c.chen@intel.com> Acked-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rui Zhang <rui.zhang@intel.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Len Brown <lenb@kernel.org> Link: https://lkml.kernel.org/r/20170913213154.070850916@linutronix.de
* | x86/apic: Sanitize return value of apic.set_apic_id()Thomas Gleixner2017-09-251-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The set_apic_id() callback returns an unsigned long value which is handed in to apic_write() as the value argument u32. Adjust the return value so it returns u32 right away. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Yu Chen <yu.c.chen@intel.com> Acked-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rui Zhang <rui.zhang@intel.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Len Brown <lenb@kernel.org> Link: https://lkml.kernel.org/r/20170913213153.437208268@linutronix.de
* x86/apic: Move cpumask and to core codeThomas Gleixner2017-06-221-1/+1
| | | | | | | | | | | | | | | | | All implementations of apic->cpu_mask_to_apicid_and() and the two incoming cpumasks to search for the target. Move that operation to the call site and rename it to cpu_mask_to_apicid() Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235446.641575516@linutronix.de
* x86/xen: Fix APIC id mismatch warning on IntelMohit Gambhir2017-01-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes the following warning message seen when booting the kernel as Dom0 with Xen on Intel machines. [0.003000] [Firmware Bug]: CPU1: APIC id mismatch. Firmware: 0 APIC: 1] The code generating the warning in validate_apic_and_package_id() matches cpu_data(cpu).apicid (initialized in init_intel()-> detect_extended_topology() using cpuid) against the apicid returned from xen_apic_read(). Now, xen_apic_read() makes a hypercall to retrieve apicid for the boot cpu but returns 0 otherwise. Hence the warning gets thrown for all but the boot cpu. The idea behind xen_apic_read() returning 0 for apicid is that the guests (even Dom0) should not need to know what physical processor their vcpus are running on. This is because we currently do not have topology information in Xen and also because xen allows more vcpus than physical processors. However, boot cpu's apicid is required for loading xen-acpi-processor driver on AMD machines. Look at following patch for details: commit 558daa289a40 ("xen/apic: Return the APIC ID (and version) for CPU 0.") So to get rid of the warning, this patch modifies xen_cpu_present_to_apicid() to return cpu_data(cpu).apicid instead of calling xen_apic_read(). The warning is not seen on AMD machines because init_amd() populates cpu_data(cpu).apicid by calling hard_smp_processor_id()->xen_apic_read() as opposed to using apicid from cpuid as is done on Intel machines. Signed-off-by: Mohit Gambhir <mohit.gambhir@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
* x86/apic: Remove the unused struct apic::apic_id_mask fieldWei Jiangang2016-07-151-1/+0
| | | | | | | | | | | | | | | | | | | | | | | The only user verify_local_APIC() had been removed by commit: 4399c03c6780 ("x86/apic: Remove verify_local_APIC()") ... so there is no need to keep it. Signed-off-by: Wei Jiangang <weijg.fnst@cn.fujitsu.com> Cc: Borislav Petkov <bp@alien8.de> 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: boris.ostrovsky@oracle.com Cc: bsd@redhat.com Cc: david.vrabel@citrix.com Cc: jgross@suse.com Cc: konrad.wilk@oracle.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1468463046-20849-1-git-send-email-weijg.fnst@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* xen/apic: Provide Xen-specific version of cpu_present_to_apicid APIC opBoris Ostrovsky2016-03-251-2/+10
| | | | | | | | | | | | | | | | | | | | | | Currently Xen uses default_cpu_present_to_apicid() which will always report BAD_APICID for PV guests since x86_bios_cpu_apic_id is initialised to that value and is never updated. With commit 1f12e32f4cd5 ("x86/topology: Create logical package id"), this op is now called by smp_init_package_map() when deciding whether to call topology_update_package_map() which sets cpu_data(cpu).logical_proc_id. The latter (as topology_logical_package_id(cpu)) may be used, for example, by cpu_to_rapl_pmu() as an array index. Since uninitialized logical_package_id is set to -1, the index will become 64K which is obviously problematic. While RAPL code (and any other users of logical_package_id) should be careful in their assumptions about id's validity, Xen's cpu_present_to_apicid op should still provide value consistent with its own xen_apic_read(APIC_ID). Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen: rename dom0_op to platform_opStefano Stabellini2015-12-211-1/+1
| | | | | | | | | The dom0_op hypercall has been renamed to platform_op since Xen 3.2, which is ancient, and modern upstream Linux kernels cannot run as dom0 and it anymore anyway. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
* xen/PMU: Intercept PMU-related MSR and APIC accessesBoris Ostrovsky2015-08-201-1/+4
| | | | | | | | | | | | Provide interfaces for recognizing accesses to PMU-related MSRs and LVTPC APIC and process these accesses in Xen PMU code. (The interrupt handler performs XENPMU_flush right away in the beginning since no PMU emulation is available. It will be added with a later patch). Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
* xen/PMU: Initialization code for Xen PMUBoris Ostrovsky2015-08-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | Map shared data structure that will hold CPU registers, VPMU context, V/PCPU IDs of the CPU interrupted by PMU interrupt. Hypervisor fills this information in its handler and passes it to the guest for further processing. Set up PMU VIRQ. Now that perf infrastructure will assume that PMU is available on a PV guest we need to be careful and make sure that accesses via RDPMC instruction don't cause fatal traps by the hypervisor. Provide a nop RDPMC handler. For the same reason avoid issuing a warning on a write to APIC's LVTPC. Both of these will be made functional in later patches. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
* x86/xen/apic: WARN with details.Konrad Rzeszutek Wilk2015-03-161-1/+1
| | | | | | | | We should not be writting to the APIC registers under Xen PV. But if we do instead of just giving an blanket warning - include some details to help troubleshoot. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* x86/xen: Provide a "Xen PV" APIC driver to support >255 VCPUsKonrad Rzeszutek Wilk2015-03-161-0/+180
| | | | | | | | | | | | | | | | | Instead of mangling the default APIC driver, provide a Xen PV guest specific one that explicitly provides appropriate methods. This allows use to report that all APIC IDs are valid, allowing dom0 to boot with more than 255 VCPUs. Since the probe order of APIC drivers is link dependent, we add in an late probe function to change to the Xen PV if it hadn't been done during bootup. Suggested-by: David Vrabel <david.vrabel@citrix.com> Reported-by: Cathy Avery <cathy.avery@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
* xen/apic/xenbus/swiotlb/pcifront/grant/tmem: Make functions or variables static.Konrad Rzeszutek Wilk2012-08-211-1/+2
| | | | | | | | | | | | There is no need for those functions/variables to be visible. Make them static and also fix the compile warnings of this sort: drivers/xen/<some file>.c: warning: symbol '<blah>' was not declared. Should it be static? Some of them just require including the header file that declares the functions. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* x86/xen/apic: Add missing #include <xen/xen.h>Ingo Molnar2012-05-181-1/+4
| | | | | | | | | | | | | | | This file depends on <xen/xen.h>, but the dependency was hidden due to: <asm/acpi.h> -> <asm/trampoline.h> -> <asm/io.h> -> <xen/xen.h> With the removal of <asm/trampoline.h>, this exposed the missing Cc: Len Brown <lenb@kernel.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/n/tip-7ccybvue6mw6wje3uxzzcglj@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* xen/apic: implement io apic read with hypercallLin Ming2012-05-011-0/+13
| | | | | | | | | | | Implements xen_io_apic_read with hypercall, so it returns proper IO-APIC information instead of fabricated one. Fallback to return an emulated IO_APIC values if hypercall fails. [v2: fallback to return an emulated IO_APIC values if hypercall fails] Signed-off-by: Lin Ming <mlin@ss.pku.edu.cn> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen/x86: Implement x86_apic_opsKonrad Rzeszutek Wilk2012-05-011-0/+17
Or rather just implement one different function as opposed to the native one : the read function. We synthesize the values. Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> [v1: Rebased on top of tip/x86/urgent] [v2: Return 0xfd instead of 0xff in the default case] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>