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2018-11-21xen: fix xen_qlock_wait()Juergen Gross
commit d3132b3860f6cf35ff7609a76bbcdbb814bd027c upstream. Commit a856531951dc80 ("xen: make xen_qlock_wait() nestable") introduced a regression for Xen guests running fully virtualized (HVM or PVH mode). The Xen hypervisor wouldn't return from the poll hypercall with interrupts disabled in case of an interrupt (for PV guests it does). So instead of disabling interrupts in xen_qlock_wait() use a nesting counter to avoid calling xen_clear_irq_pending() in case xen_qlock_wait() is nested. Fixes: a856531951dc80 ("xen: make xen_qlock_wait() nestable") Cc: stable@vger.kernel.org Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21xen: make xen_qlock_wait() nestableJuergen Gross
commit a856531951dc8094359dfdac21d59cee5969c18e upstream. xen_qlock_wait() isn't safe for nested calls due to interrupts. A call of xen_qlock_kick() might be ignored in case a deeper nesting level was active right before the call of xen_poll_irq(): CPU 1: CPU 2: spin_lock(lock1) spin_lock(lock1) -> xen_qlock_wait() -> xen_clear_irq_pending() Interrupt happens spin_unlock(lock1) -> xen_qlock_kick(CPU 2) spin_lock_irqsave(lock2) spin_lock_irqsave(lock2) -> xen_qlock_wait() -> xen_clear_irq_pending() clears kick for lock1 -> xen_poll_irq() spin_unlock_irq_restore(lock2) -> xen_qlock_kick(CPU 2) wakes up spin_unlock_irq_restore(lock2) IRET resumes in xen_qlock_wait() -> xen_poll_irq() never wakes up The solution is to disable interrupts in xen_qlock_wait() and not to poll for the irq in case xen_qlock_wait() is called in nmi context. Cc: stable@vger.kernel.org Cc: Waiman.Long@hp.com Cc: peterz@infradead.org Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21xen: fix race in xen_qlock_wait()Juergen Gross
commit 2ac2a7d4d9ff4e01e36f9c3d116582f6f655ab47 upstream. In the following situation a vcpu waiting for a lock might not be woken up from xen_poll_irq(): CPU 1: CPU 2: CPU 3: takes a spinlock tries to get lock -> xen_qlock_wait() frees the lock -> xen_qlock_kick(cpu2) -> xen_clear_irq_pending() takes lock again tries to get lock -> *lock = _Q_SLOW_VAL -> *lock == _Q_SLOW_VAL ? -> xen_poll_irq() frees the lock -> xen_qlock_kick(cpu3) And cpu 2 will sleep forever. This can be avoided easily by modifying xen_qlock_wait() to call xen_poll_irq() only if the related irq was not pending and to call xen_clear_irq_pending() only if it was pending. Cc: stable@vger.kernel.org Cc: Waiman.Long@hp.com Cc: peterz@infradead.org Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-29xen/x86/vpmu: Zero struct pt_regs before calling into sample handling codeBoris Ostrovsky
commit 70513d58751d7c6c1a0133557b13089b9f2e3e66 upstream. Otherwise we may leak kernel stack for events that sample user registers. Reported-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-25x86/xen: Add call of speculative_store_bypass_ht_init() to PV pathsJuergen Gross
commit 74899d92e66663dc7671a8017b3146dcd4735f3b upstream. Commit: 1f50ddb4f418 ("x86/speculation: Handle HT correctly on AMD") ... added speculative_store_bypass_ht_init() to the per-CPU initialization sequence. speculative_store_bypass_ht_init() needs to be called on each CPU for PV guests, too. Reported-by: Brian Woods <brian.woods@amd.com> Tested-by: Brian Woods <brian.woods@amd.com> Signed-off-by: Juergen Gross <jgross@suse.com> Cc: <stable@vger.kernel.org> 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: xen-devel@lists.xenproject.org Fixes: 1f50ddb4f4189243c05926b842dc1a0332195f31 ("x86/speculation: Handle HT correctly on AMD") Link: https://lore.kernel.org/lkml/20180621084331.21228-1-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-25x86/amd: don't set X86_BUG_SYSRET_SS_ATTRS when running under XenDavid Woodhouse
commit def9331a12977770cc6132d79f8e6565871e8e38 upstream When running as Xen pv guest X86_BUG_SYSRET_SS_ATTRS must not be set on AMD cpus. This bug/feature bit is kind of special as it will be used very early when switching threads. Setting the bit and clearing it a little bit later leaves a critical window where things can go wrong. This time window has enlarged a little bit by using setup_clear_cpu_cap() instead of the hypervisor's set_cpu_features callback. It seems this larger window now makes it rather easy to hit the problem. The proper solution is to never set the bit in case of Xen. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com> Reviewed-by: Alexey Makhalov <amakhalov@vmware.com> Reviewed-by: Bo Gan <ganb@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-25xen: set cpu capabilities from xen_start_kernel()Juergen Gross
Upstream commit: 0808e80cb760de2733c0527d2090ed2205a1eef8 ("xen: set cpu capabilities from xen_start_kernel()") There is no need to set the same capabilities for each cpu individually. This can easily be done for all cpus when starting the kernel. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com> Reviewed-by: Alexey Makhalov <amakhalov@vmware.com> Reviewed-by: Bo Gan <ganb@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-25x86/xen: Zero MSR_IA32_SPEC_CTRL before suspendJuergen Gross
commit 71c208dd54ab971036d83ff6d9837bae4976e623 upstream. Older Xen versions (4.5 and before) might have problems migrating pv guests with MSR_IA32_SPEC_CTRL having a non-zero value. So before suspending zero that MSR and restore it after being resumed. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jan Beulich <jbeulich@suse.com> Cc: stable@vger.kernel.org Cc: xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com Link: https://lkml.kernel.org/r/20180226140818.4849-1-jgross@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com> Reviewed-by: Alexey Makhalov <amakhalov@vmware.com> Reviewed-by: Bo Gan <ganb@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26tracing/x86/xen: Remove zero data size trace events ↵Steven Rostedt (VMware)
trace_xen_mmu_flush_tlb{_all} commit 45dd9b0666a162f8e4be76096716670cf1741f0e upstream. Doing an audit of trace events, I discovered two trace events in the xen subsystem that use a hack to create zero data size trace events. This is not what trace events are for. Trace events add memory footprint overhead, and if all you need to do is see if a function is hit or not, simply make that function noinline and use function tracer filtering. Worse yet, the hack used was: __array(char, x, 0) Which creates a static string of zero in length. There's assumptions about such constructs in ftrace that this is a dynamic string that is nul terminated. This is not the case with these tracepoints and can cause problems in various parts of ftrace. Nuke the trace events! Link: http://lkml.kernel.org/r/20180509144605.5a220327@gandalf.local.home Cc: stable@vger.kernel.org Fixes: 95a7d76897c1e ("xen/mmu: Use Xen specific TLB flush instead of the generic one.") Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02x86/mm: Enable CR4.PCIDE on supported systemsAndy Lutomirski
commit 660da7c9228f685b2ebe664f9fd69aaddcc420b5 upstream. We can use PCID if the CPU has PCID and PGE and we're not on Xen. By itself, this has no effect. A followup patch will start using PCID. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Nadav Amit <nadav.amit@gmail.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/6327ecd907b32f79d5aa0d466f04503bbec5df88.1498751203.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-20xen: adjust early dom0 p2m handling to xen hypervisor behaviorJuergen Gross
commit 69861e0a52f8733355ce246f0db15e1b240ad667 upstream. When booted as pv-guest the p2m list presented by the Xen is already mapped to virtual addresses. In dom0 case the hypervisor might make use of 2M- or 1G-pages for this mapping. Unfortunately while being properly aligned in virtual and machine address space, those pages might not be aligned properly in guest physical address space. So when trying to obtain the guest physical address of such a page pud_pfn() and pmd_pfn() must be avoided as those will mask away guest physical address bits not being zero in this special case. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-02xen/x86: don't lose event interruptsStefano Stabellini
commit c06b6d70feb32d28f04ba37aa3df17973fd37b6b upstream. On slow platforms with unreliable TSC, such as QEMU emulated machines, it is possible for the kernel to request the next event in the past. In that case, in the current implementation of xen_vcpuop_clockevent, we simply return -ETIME. To be precise the Xen returns -ETIME and we pass it on. However the result of this is a missed event, which simply causes the kernel to hang. Instead it is better to always ask the hypervisor for a timer event, even if the timeout is in the past. That way there are no lost interrupts and the kernel survives. To do that, remove the VCPU_SSHOTTMR_future flag. Signed-off-by: Stefano Stabellini <sstabellini@kernel.org> Acked-by: Juergen Gross <jgross@suse.com> Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08xen/setup: Don't relocate p2m over existing oneRoss Lagerwall
commit 7ecec8503af37de6be4f96b53828d640a968705f upstream. When relocating the p2m, take special care not to relocate it so that is overlaps with the current location of the p2m/initrd. This is needed since the full extent of the current location is not marked as a reserved region in the e820. This was seen to happen to a dom0 with a large initial p2m and a small reserved region in the middle of the initial p2m. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-26xen/qspinlock: Don't kick CPU if IRQ is not initializedRoss Lagerwall
commit 707e59ba494372a90d245f18b0c78982caa88e48 upstream. The following commit: 1fb3a8b2cfb2 ("xen/spinlock: Fix locking path engaging too soon under PVHVM.") ... moved the initalization of the kicker interrupt until after native_cpu_up() is called. However, when using qspinlocks, a CPU may try to kick another CPU that is spinning (because it has not yet initialized its kicker interrupt), resulting in the following crash during boot: kernel BUG at /build/linux-Ay7j_C/linux-4.4.0/drivers/xen/events/events_base.c:1210! invalid opcode: 0000 [#1] SMP ... RIP: 0010:[<ffffffff814c97c9>] [<ffffffff814c97c9>] xen_send_IPI_one+0x59/0x60 ... Call Trace: [<ffffffff8102be9e>] xen_qlock_kick+0xe/0x10 [<ffffffff810cabc2>] __pv_queued_spin_unlock+0xb2/0xf0 [<ffffffff810ca6d1>] ? __raw_callee_save___pv_queued_spin_unlock+0x11/0x20 [<ffffffff81052936>] ? check_tsc_warp+0x76/0x150 [<ffffffff81052aa6>] check_tsc_sync_source+0x96/0x160 [<ffffffff81051e28>] native_cpu_up+0x3d8/0x9f0 [<ffffffff8102b315>] xen_hvm_cpu_up+0x35/0x80 [<ffffffff8108198c>] _cpu_up+0x13c/0x180 [<ffffffff81081a4a>] cpu_up+0x7a/0xa0 [<ffffffff81f80dfc>] smp_init+0x7f/0x81 [<ffffffff81f5a121>] kernel_init_freeable+0xef/0x212 [<ffffffff81817f30>] ? rest_init+0x80/0x80 [<ffffffff81817f3e>] kernel_init+0xe/0xe0 [<ffffffff8182488f>] ret_from_fork+0x3f/0x70 [<ffffffff81817f30>] ? rest_init+0x80/0x80 To fix this, only send the kick if the target CPU's interrupt has been initialized. This check isn't racy, because the target is waiting for the spinlock, so it won't have initialized the interrupt in the meantime. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-10x86/xen: fix upper bound of pmd loop in xen_cleanhighmap()Juergen Gross
commit 1cf38741308c64d08553602b3374fb39224eeb5a upstream. xen_cleanhighmap() is operating on level2_kernel_pgt only. The upper bound of the loop setting non-kernel-image entries to zero should not exceed the size of level2_kernel_pgt. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/xen, pat: Remove PAT table init code from XenToshi Kani
commit 88ba281108ed0c25c9d292b48bd3f272fcb90dd0 upstream. Xen supports PAT without MTRRs for its guests. In order to enable WC attribute, it was necessary for xen_start_kernel() to call pat_init_cache_modes() to update PAT table before starting guest kernel. Now that the kernel initializes PAT table to the BIOS handoff state when MTRR is disabled, this Xen-specific PAT init code is no longer necessary. Delete it from xen_start_kernel(). Also change __init_cache_modes() to a static function since PAT table should not be tweaked by other modules. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Juergen Gross <jgross@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Toshi Kani <toshi.kani@hp.com> Cc: elliott@hpe.com Cc: paul.gortmaker@windriver.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1458769323-24491-7-git-send-email-toshi.kani@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16x86/mm/pat: Add support of non-default PAT MSR settingToshi Kani
commit 02f037d641dc6672be5cfe7875a48ab99b95b154 upstream. In preparation for fixing a regression caused by: 9cd25aac1f44 ("x86/mm/pat: Emulate PAT when it is disabled")' ... PAT needs to support a case that PAT MSR is initialized with a non-default value. When pat_init() is called and PAT is disabled, it initializes the PAT table with the BIOS default value. Xen, however, sets PAT MSR with a non-default value to enable WC. This causes inconsistency between the PAT table and PAT MSR when PAT is set to disable on Xen. Change pat_init() to handle the PAT disable cases properly. Add init_cache_modes() to handle two cases when PAT is set to disable. 1. CPU supports PAT: Set PAT table to be consistent with PAT MSR. 2. CPU does not support PAT: Set PAT table to be consistent with PWT and PCD bits in a PTE. Note, __init_cache_modes(), renamed from pat_init_cache_modes(), will be changed to a static function in a later patch. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Toshi Kani <toshi.kani@hp.com> Cc: elliott@hpe.com Cc: konrad.wilk@oracle.com Cc: paul.gortmaker@windriver.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1458769323-24491-2-git-send-email-toshi.kani@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-07xen: use same main loop for counting and remapping pagesJuergen Gross
commit dd14be92fbf5bc1ef7343f34968440e44e21b46a upstream. Instead of having two functions for cycling through the E820 map in order to count to be remapped pages and remap them later, just use one function with a caller supplied sub-function called for each region to be processed. This eliminates the possibility of a mismatch between both loops which showed up in certain configurations. Suggested-by: Ed Swierk <eswierk@skyportsystems.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12x86/iopl/64: Properly context-switch IOPL on Xen PVAndy Lutomirski
commit b7a584598aea7ca73140cb87b40319944dd3393f upstream. On Xen PV, regs->flags doesn't reliably reflect IOPL and the exit-to-userspace code doesn't change IOPL. We need to context switch it manually. I'm doing this without going through paravirt because this is specific to Xen PV. After the dust settles, we can merge this with the 32-bit code, tidy up the iopl syscall implementation, and remove the set_iopl pvop entirely. Fixes XSA-171. Reviewewd-by: Jan Beulich <JBeulich@suse.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <JBeulich@suse.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/693c3bd7aeb4d3c27c92c622b7d0f554a458173c.1458162709.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31x86/xen: don't reset vcpu_info on a cancelled suspendOuyang Zhaowei (Charles)
commit 6a1f513776b78c994045287073e55bae44ed9f8c upstream. On a cancelled suspend the vcpu_info location does not change (it's still in the per-cpu area registered by xen_vcpu_setup()). So do not call xen_hvm_init_shared_info() which would make the kernel think its back in the shared info. With the wrong vcpu_info, events cannot be received and the domain will hang after a cancelled suspend. Signed-off-by: Charles Ouyang <ouyangzhaowei@huawei.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-08Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "A handful of x86 fixes: - a syscall ABI fix, fixing an Android breakage - a Xen PV guest fix relating to the RTC device, causing a non-working console - a Xen guest syscall stack frame fix - an MCE hotplug CPU crash fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/numachip: Fix NumaConnect2 MMCFG PCI access x86/entry: Restore traditional SYSENTER calling convention x86/entry: Fix some comments x86/paravirt: Prevent rtc_cmos platform device init on PV guests x86/xen: Avoid fast syscall path for Xen PV guests x86/mce: Ensure offline CPUs don't participate in rendezvous process
2015-12-29arch/x86/xen/suspend.c: include xen/xen.hAndrew Morton
Fix the build warning: arch/x86/xen/suspend.c: In function 'xen_arch_pre_suspend': arch/x86/xen/suspend.c:70:9: error: implicit declaration of function 'xen_pv_domain' [-Werror=implicit-function-declaration] if (xen_pv_domain()) ^ Reported-by: kbuild test robot <fengguang.wu@intel.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-19x86/paravirt: Prevent rtc_cmos platform device init on PV guestsDavid Vrabel
Adding the rtc platform device in non-privileged Xen PV guests causes an IRQ conflict because these guests do not have legacy PIC and may allocate irqs in the legacy range. In a single VCPU Xen PV guest we should have: /proc/interrupts: CPU0 0: 4934 xen-percpu-virq timer0 1: 0 xen-percpu-ipi spinlock0 2: 0 xen-percpu-ipi resched0 3: 0 xen-percpu-ipi callfunc0 4: 0 xen-percpu-virq debug0 5: 0 xen-percpu-ipi callfuncsingle0 6: 0 xen-percpu-ipi irqwork0 7: 321 xen-dyn-event xenbus 8: 90 xen-dyn-event hvc_console ... But hvc_console cannot get its interrupt because it is already in use by rtc0 and the console does not work. genirq: Flags mismatch irq 8. 00000000 (hvc_console) vs. 00000000 (rtc0) We can avoid this problem by realizing that unprivileged PV guests (both Xen and lguests) are not supposed to have rtc_cmos device and so adding it is not necessary. Privileged guests (i.e. Xen's dom0) do use it but they should not have irq conflicts since they allocate irqs above legacy range (above gsi_top, in fact). Instead of explicitly testing whether the guest is privileged we can extend pv_info structure to include information about guest's RTC support. Reported-and-tested-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: vkuznets@redhat.com Cc: xen-devel@lists.xenproject.org Cc: konrad.wilk@oracle.com Cc: stable@vger.kernel.org # 4.2+ Link: http://lkml.kernel.org/r/1449842873-2613-1-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-19x86/xen: Avoid fast syscall path for Xen PV guestsBoris Ostrovsky
After 32-bit syscall rewrite, and specifically after commit: 5f310f739b4c ("x86/entry/32: Re-implement SYSENTER using the new C path") ... the stack frame that is passed to xen_sysexit is no longer a "standard" one (i.e. it's not pt_regs). Since we end up calling xen_iret from xen_sysexit we don't need to fix up the stack and instead follow entry_SYSENTER_32's IRET path directly to xen_iret. We can do the same thing for compat mode even though stack does not need to be fixed. This will allow us to drop usergs_sysret32 paravirt op (in the subsequent patch) Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> 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: david.vrabel@citrix.com Cc: konrad.wilk@oracle.com Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1447970147-1733-2-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-18Merge tag 'for-linus-4.4-rc5-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen bug fixes from David Vrabel: - XSA-155 security fixes to backend drivers. - XSA-157 security fixes to pciback. * tag 'for-linus-4.4-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen-pciback: fix up cleanup path when alloc fails xen/pciback: Don't allow MSI-X ops if PCI_COMMAND_MEMORY is not set. xen/pciback: For XEN_PCI_OP_disable_msi[|x] only disable if device has MSI(X) enabled. xen/pciback: Do not install an IRQ handler for MSI interrupts. xen/pciback: Return error on XEN_PCI_OP_enable_msix when device has MSI or MSI-X enabled xen/pciback: Return error on XEN_PCI_OP_enable_msi when device has MSI or MSI-X enabled xen/pciback: Save xen_pci_op commands before processing it xen-scsiback: safely copy requests xen-blkback: read from indirect descriptors only once xen-blkback: only read request operation from shared ring once xen-netback: use RING_COPY_REQUEST() throughout xen-netback: don't use last request to determine minimum Tx credit xen: Add RING_COPY_REQUEST() xen/x86/pvh: Use HVM's flush_tlb_others op xen: Resume PMU from non-atomic context xen/events/fifo: Consume unprocessed events when a CPU dies
2015-12-14xen/x86/pvh: Use HVM's flush_tlb_others opBoris Ostrovsky
Using MMUEXT_TLB_FLUSH_MULTI doesn't buy us much since the hypervisor will likely perform same IPIs as would have the guest. More importantly, using MMUEXT_INVLPG_MULTI may not to invalidate the guest's address on remote CPU (when, for example, VCPU from another guest is running there). Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Suggested-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-12-02xen: Resume PMU from non-atomic contextBoris Ostrovsky
Resuming PMU currently triggers a warning from ___might_sleep() (assuming CONFIG_DEBUG_ATOMIC_SLEEP is set) when xen_pmu_init() allocates GFP_KERNEL page because we are in state resembling atomic context. Move resuming PMU to xen_arch_resume() which is called in regular context. For symmetry move suspending PMU to xen_arch_suspend() as well. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: <stable@vger.kernel.org> # 4.3 Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-11-04Merge tag 'for-linus-4.4-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from David Vrabel: - Improve balloon driver memory hotplug placement. - Use unpopulated hotplugged memory for foreign pages (if supported/enabled). - Support 64 KiB guest pages on arm64. - CPU hotplug support on arm/arm64. * tag 'for-linus-4.4-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (44 commits) xen: fix the check of e_pfn in xen_find_pfn_range x86/xen: add reschedule point when mapping foreign GFNs xen/arm: don't try to re-register vcpu_info on cpu_hotplug. xen, cpu_hotplug: call device_offline instead of cpu_down xen/arm: Enable cpu_hotplug.c xenbus: Support multiple grants ring with 64KB xen/grant-table: Add an helper to iterate over a specific number of grants xen/xenbus: Rename *RING_PAGE* to *RING_GRANT* xen/arm: correct comment in enlighten.c xen/gntdev: use types from linux/types.h in userspace headers xen/gntalloc: use types from linux/types.h in userspace headers xen/balloon: Use the correct sizeof when declaring frame_list xen/swiotlb: Add support for 64KB page granularity xen/swiotlb: Pass addresses rather than frame numbers to xen_arch_need_swiotlb arm/xen: Add support for 64KB page granularity xen/privcmd: Add support for Linux 64KB page granularity net/xen-netback: Make it running on 64KB page granularity net/xen-netfront: Make it running on 64KB page granularity block/xen-blkback: Make it running on 64KB page granularity block/xen-blkfront: Make it running on 64KB page granularity ...
2015-11-02xen: fix the check of e_pfn in xen_find_pfn_rangeZhenzhong Duan
On some NUMA system, after dom0 up, we see below warning even if there are enough pfn ranges that could be used for remapping: "Unable to find available pfn range, not remapping identity pages" Fix it to avoid getting a memory region of zero size in xen_find_pfn_range. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-28x86/xen: add reschedule point when mapping foreign GFNsDavid Vrabel
Mapping a large range of foreign GFNs can take a long time, add a reschedule point after each batch of 16 GFNs. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2015-10-23xen/arm: Enable cpu_hotplug.cStefano Stabellini
Build cpu_hotplug for ARM and ARM64 guests. Rename arch_(un)register_cpu to xen_(un)register_cpu and provide an empty implementation on ARM and ARM64. On x86 just call arch_(un)register_cpu as we are already doing. Initialize cpu_hotplug on ARM. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2015-10-23x86/xen: export xen_alloc_p2m_entry()David Vrabel
Rename alloc_p2m() to xen_alloc_p2m_entry() and export it. This is useful for ensuring that a p2m entry is allocated (i.e., not a shared missing or identity entry) so that subsequent set_phys_to_machine() calls will require no further allocations. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> --- v3: - Make xen_alloc_p2m_entry() a nop on auto-xlate guests.
2015-10-23xen/balloon: make alloc_xenballoon_pages() always allocate low pagesDavid Vrabel
All users of alloc_xenballoon_pages() wanted low memory pages, so remove the option for high memory. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2015-10-23x86/xen: discard RAM regions above the maximum reservationDavid Vrabel
During setup, discard RAM regions that are above the maximum reservation (instead of marking them as E820_UNUSABLE). This allows hotplug memory to be placed at these addresses. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2015-10-07x86/vdso: Remove runtime 32-bit vDSO selectionAndy Lutomirski
32-bit userspace will now always see the same vDSO, which is exactly what used to be the int80 vDSO. Subsequent patches will clean it up and make it support SYSENTER and SYSCALL using alternatives. Signed-off-by: Andy Lutomirski <luto@kernel.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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/e7e6b3526fa442502e6125fe69486aab50813c32.1444091584.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-06x86/xen/p2m: hint at the last populated P2M entryDavid Vrabel
With commit 633d6f17cd91ad5bf2370265946f716e42d388c6 (x86/xen: prepare p2m list for memory hotplug) the P2M may be sized to accomdate a much larger amount of memory than the domain currently has. When saving a domain, the toolstack must scan all the P2M looking for populated pages. This results in a performance regression due to the unnecessary scanning. Instead of reporting (via shared_info) the maximum possible size of the P2M, hint at the last PFN which might be populated. This hint is increased as new leaves are added to the P2M (in the expectation that they will be used for populated entries). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: <stable@vger.kernel.org> # 4.0+
2015-09-28x86/xen: Do not clip xen_e820_map to xen_e820_map_entries when sanitizing mapMalcolm Crossley
Sanitizing the e820 map may produce extra E820 entries which would result in the topmost E820 entries being removed. The removed entries would typically include the top E820 usable RAM region and thus result in the domain having signicantly less RAM available to it. Fix by allowing sanitize_e820_map to use the full size of the allocated E820 array. Signed-off-by: Malcolm Crossley <malcolm.crossley@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-28x86/xen: Support kexec/kdump in HVM guests by doing a soft resetVitaly Kuznetsov
Currently there is a number of issues preventing PVHVM Xen guests from doing successful kexec/kdump: - Bound event channels. - Registered vcpu_info. - PIRQ/emuirq mappings. - shared_info frame after XENMAPSPACE_shared_info operation. - Active grant mappings. Basically, newly booted kernel stumbles upon already set up Xen interfaces and there is no way to reestablish them. In Xen-4.7 a new feature called 'soft reset' is coming. A guest performing kexec/kdump operation is supposed to call SCHEDOP_shutdown hypercall with SHUTDOWN_soft_reset reason before jumping to new kernel. Hypervisor (with some help from toolstack) will do full domain cleanup (but keeping its memory and vCPU contexts intact) returning the guest to the state it had when it was first booted and thus allowing it to start over. Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is probably OK as by default all unknown shutdown reasons cause domain destroy with a message in toolstack log: 'Unknown shutdown reason code 5. Destroying domain.' which gives a clue to what the problem is and eliminates false expectations. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-28xen/x86: Don't try to write syscall-related MSRs for PV guestsBoris Ostrovsky
For PV guests these registers are set up by hypervisor and thus should not be written by the guest. The comment in xen_write_msr_safe() says so but we still write the MSRs, causing the hypervisor to print a warning. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-28xen: use correct type for HYPERVISOR_memory_op()Juergen Gross
HYPERVISOR_memory_op() is defined to return an "int" value. This is wrong, as the Xen hypervisor will return "long". The sub-function XENMEM_maximum_reservation returns the maximum number of pages for the current domain. An int will overflow for a domain configured with 8TB of memory or more. Correct this by using the correct type. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-10Merge tag 'for-linus-4.3-rc0b-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen terminology fixes from David Vrabel: "Use the correct GFN/BFN terms more consistently" * tag 'for-linus-4.3-rc0b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/xenbus: Rename the variable xen_store_mfn to xen_store_gfn xen/privcmd: Further s/MFN/GFN/ clean-up hvc/xen: Further s/MFN/GFN clean-up video/xen-fbfront: Further s/MFN/GFN clean-up xen/tmem: Use xen_page_to_gfn rather than pfn_to_gfn xen: Use correctly the Xen memory terminologies arm/xen: implement correctly pfn_to_mfn xen: Make clear that swiotlb and biomerge are dealing with DMA address
2015-09-08Merge tag 'for-linus-4.3-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from David Vrabel: "Xen features and fixes for 4.3: - Convert xen-blkfront to the multiqueue API - [arm] Support binding event channels to different VCPUs. - [x86] Support > 512 GiB in a PV guests (off by default as such a guest cannot be migrated with the current toolstack). - [x86] PMU support for PV dom0 (limited support for using perf with Xen and other guests)" * tag 'for-linus-4.3-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (33 commits) xen: switch extra memory accounting to use pfns xen: limit memory to architectural maximum xen: avoid another early crash of memory limited dom0 xen: avoid early crash of memory limited dom0 arm/xen: Remove helpers which are PV specific xen/x86: Don't try to set PCE bit in CR4 xen/PMU: PMU emulation code xen/PMU: Intercept PMU-related MSR and APIC accesses xen/PMU: Describe vendor-specific PMU registers xen/PMU: Initialization code for Xen PMU xen/PMU: Sysfs interface for setting Xen PMU mode xen: xensyms support xen: remove no longer needed p2m.h xen: allow more than 512 GB of RAM for 64 bit pv-domains xen: move p2m list if conflicting with e820 map xen: add explicit memblock_reserve() calls for special pages mm: provide early_memremap_ro to establish read-only mapping xen: check for initrd conflicting with e820 map xen: check pre-allocated page tables for conflict with memory map xen: check for kernel memory conflicting with memory layout ...
2015-09-08xen/privcmd: Further s/MFN/GFN/ clean-upJulien Grall
The privcmd code is mixing the usage of GFN and MFN within the same functions which make the code difficult to understand when you only work with auto-translated guests. The privcmd driver is only dealing with GFN so replace all the mention of MFN into GFN. The ioctl structure used to map foreign change has been left unchanged given that the userspace is using it. Nonetheless, add a comment to explain the expected value within the "mfn" field. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08xen: Use correctly the Xen memory terminologiesJulien Grall
Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN is meant, I suspect this is because the first support for Xen was for PV. This resulted in some misimplementation of helpers on ARM and confused developers about the expected behavior. For instance, with pfn_to_mfn, we expect to get an MFN based on the name. Although, if we look at the implementation on x86, it's returning a GFN. For clarity and avoid new confusion, replace any reference to mfn with gfn in any helpers used by PV drivers. The x86 code will still keep some reference of pfn_to_mfn which may be used by all kind of guests No changes as been made in the hypercall field, even though they may be invalid, in order to keep the same as the defintion in xen repo. Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a name to close to the KVM function gfn_to_page. Take also the opportunity to simplify simple construction such as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up will come in follow-up patches. [1] http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cb Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08xen: switch extra memory accounting to use pfnsJuergen Gross
Instead of using physical addresses for accounting of extra memory areas available for ballooning switch to pfns as this is much less error prone regarding partial pages. Reported-by: Roger Pau Monné <roger.pau@citrix.com> Tested-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08xen: limit memory to architectural maximumJuergen Gross
When a pv-domain (including dom0) is started it tries to size it's p2m list according to the maximum possible memory amount it ever can achieve. Limit the initial maximum memory size to the architectural limit of the hardware in order to avoid overflows during remapping of memory. This problem will occur when dom0 is started with an initial memory size being a multiple of 1GB, but without specifying it's maximum memory size. The kernel must be configured without CONFIG_XEN_BALLOON_MEMORY_HOTPLUG for the problem to happen. Reported-by: Roger Pau Monné <roger.pau@citrix.com> Tested-by: Roger Pau Monné <roger.pau@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08xen: avoid another early crash of memory limited dom0Juergen Gross
Commit b1c9f169047b ("xen: split counting of extra memory pages...") introduced an error when dom0 was started with limited memory occurring only on some hardware. The problem arises in case dom0 is started with initial memory and maximum memory being the same. The kernel must be configured without CONFIG_XEN_BALLOON_MEMORY_HOTPLUG for the problem to happen. If all of this is true and the E820 map of the machine is sparse (some areas are not covered) then the machine might crash early in the boot process. An example E820 map triggering the problem looks like this: [ 0.000000] e820: BIOS-provided physical RAM map: [ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009d7ff] usable [ 0.000000] BIOS-e820: [mem 0x000000000009d800-0x000000000009ffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000000e0000-0x00000000000fffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x00000000cf7fafff] usable [ 0.000000] BIOS-e820: [mem 0x00000000cf7fb000-0x00000000cf95ffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000cf960000-0x00000000cfb62fff] ACPI NVS [ 0.000000] BIOS-e820: [mem 0x00000000cfb63000-0x00000000cfd14fff] usable [ 0.000000] BIOS-e820: [mem 0x00000000cfd15000-0x00000000cfd61fff] ACPI NVS [ 0.000000] BIOS-e820: [mem 0x00000000cfd62000-0x00000000cfd6cfff] ACPI data [ 0.000000] BIOS-e820: [mem 0x00000000cfd6d000-0x00000000cfd6ffff] ACPI NVS [ 0.000000] BIOS-e820: [mem 0x00000000cfd70000-0x00000000cfd70fff] usable [ 0.000000] BIOS-e820: [mem 0x00000000cfd71000-0x00000000cfea8fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000cfea9000-0x00000000cfeb9fff] ACPI NVS [ 0.000000] BIOS-e820: [mem 0x00000000cfeba000-0x00000000cfecafff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000cfecb000-0x00000000cfecbfff] ACPI NVS [ 0.000000] BIOS-e820: [mem 0x00000000cfecc000-0x00000000cfedbfff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000cfedc000-0x00000000cfedcfff] ACPI NVS [ 0.000000] BIOS-e820: [mem 0x00000000cfedd000-0x00000000cfeddfff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000cfede000-0x00000000cfee3fff] ACPI NVS [ 0.000000] BIOS-e820: [mem 0x00000000cfee4000-0x00000000cfef6fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000cfef7000-0x00000000cfefffff] usable [ 0.000000] BIOS-e820: [mem 0x00000000e0000000-0x00000000efffffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fec00000-0x00000000fec00fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fec10000-0x00000000fec10fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fed00000-0x00000000fed00fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fed40000-0x00000000fed44fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fed61000-0x00000000fed70fff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000fed80000-0x00000000fed8ffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000ff000000-0x00000000ffffffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000000100001000-0x000000020effffff] usable In this case the area a0000-dffff isn't present in the map. This will confuse the memory setup of the domain when remapping the memory from such holes to populated areas. To avoid the problem the accounting of to be remapped memory has to count such holes in the E820 map as well. Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08xen: avoid early crash of memory limited dom0Juergen Gross
Commit b1c9f169047b ("xen: split counting of extra memory pages...") introduced an error when dom0 was started with limited memory. The problem arises in case dom0 is started with initial memory and maximum memory being the same and exactly a multiple of 1 GB. The kernel must be configured without CONFIG_XEN_BALLOON_MEMORY_HOTPLUG for the problem to happen. In this case it will crash very early during boot due to the virtual mapped p2m list not being large enough to be able to remap any memory: (XEN) Freed 304kB init memory. mapping kernel into physical memory about to get started... (XEN) traps.c:459:d0v0 Unhandled invalid opcode fault/trap [#6] on VCPU 0 [ec=0000] (XEN) domain_crash_sync called from entry.S: fault at ffff82d080229a93 create_bounce_frame+0x12b/0x13a (XEN) Domain 0 (vcpu#0) crashed on cpu#0: (XEN) ----[ Xen-4.5.2-pre x86_64 debug=n Not tainted ]---- (XEN) CPU: 0 (XEN) RIP: e033:[<ffffffff81d120cb>] (XEN) RFLAGS: 0000000000000206 EM: 1 CONTEXT: pv guest (d0v0) (XEN) rax: ffffffff81db2000 rbx: 000000004d000000 rcx: 0000000000000000 (XEN) rdx: 000000004d000000 rsi: 0000000000063000 rdi: 000000004d063000 (XEN) rbp: ffffffff81c03d78 rsp: ffffffff81c03d28 r8: 0000000000023000 (XEN) r9: 00000001040ff000 r10: 0000000000007ff0 r11: 0000000000000000 (XEN) r12: 0000000000063000 r13: 000000000004d000 r14: 0000000000000063 (XEN) r15: 0000000000000063 cr0: 0000000080050033 cr4: 00000000000006f0 (XEN) cr3: 0000000105c0f000 cr2: ffffc90000268000 (XEN) ds: 0000 es: 0000 fs: 0000 gs: 0000 ss: e02b cs: e033 (XEN) Guest stack trace from rsp=ffffffff81c03d28: (XEN) 0000000000000000 0000000000000000 ffffffff81d120cb 000000010000e030 (XEN) 0000000000010006 ffffffff81c03d68 000000000000e02b ffffffffffffffff (XEN) 0000000000000063 000000000004d063 ffffffff81c03de8 ffffffff81d130a7 (XEN) ffffffff81c03de8 000000000004d000 00000001040ff000 0000000000105db1 (XEN) 00000001040ff001 000000000004d062 ffff8800092d6ff8 0000000002027000 (XEN) ffff8800094d8340 ffff8800092d6ff8 00003ffffffff000 ffff8800092d7ff8 (XEN) ffffffff81c03e48 ffffffff81d13c43 ffff8800094d8000 ffff8800094d9000 (XEN) 0000000000000000 ffff8800092d6000 00000000092d6000 000000004cfbf000 (XEN) 00000000092d6000 00000000052d5442 0000000000000000 0000000000000000 (XEN) ffffffff81c03ed8 ffffffff81d185c1 0000000000000000 0000000000000000 (XEN) ffffffff81c03e78 ffffffff810f8ca4 ffffffff81c03ed8 ffffffff8171a15d (XEN) 0000000000000010 ffffffff81c03ee8 0000000000000000 0000000000000000 (XEN) ffffffff81f0e402 ffffffffffffffff ffffffff81dae900 0000000000000000 (XEN) 0000000000000000 0000000000000000 ffffffff81c03f28 ffffffff81d0cf0f (XEN) 0000000000000000 0000000000000000 0000000000000000 ffffffff81db82e0 (XEN) 0000000000000000 0000000000000000 0000000000000000 0000000000000000 (XEN) ffffffff81c03f38 ffffffff81d0c603 ffffffff81c03ff8 ffffffff81d11c86 (XEN) 0300000100000032 0000000000000005 0000000000000020 0000000000000000 (XEN) 0000000000000000 0000000000000000 0000000000000000 0000000000000000 (XEN) 0000000000000000 0000000000000000 0000000000000000 0000000000000000 (XEN) Domain 0 crashed: rebooting machine in 5 seconds. This can be avoided by allocating aneough space for the p2m to cover the maximum memory of dom0 plus the identity mapped holes required for PCI space, BIOS etc. Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-01Merge branch 'x86-platform-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core platform updates from Ingo Molnar: "The main changes are: - Intel Atom platform updates. (Andy Shevchenko) - modularity fixlets. (Paul Gortmaker) - x86 platform clockevents driver updates for lguest, uv and Xen. (Viresh Kumar) - Microsoft Hyper-V TSC fixlet. (Vitaly Kuznetsov)" * 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/platform: Make atom/pmc_atom.c explicitly non-modular x86/hyperv: Mark the Hyper-V TSC as unstable x86/xen/time: Migrate to new set-state interface x86/uv/time: Migrate to new set-state interface x86/lguest/timer: Migrate to new set-state interface x86/pci/intel_mid_pci: Use proper constants for irq polarity x86/pci/intel_mid_pci: Make intel_mid_pci_ops static x86/pci/intel_mid_pci: Propagate actual return code x86/pci/intel_mid_pci: Work around for IRQ0 assignment x86/platform/iosf_mbi: Add Intel Tangier PCI id x86/platform/iosf_mbi: Source cleanup x86/platform/iosf_mbi: Remove NULL pointer checks for pci_dev_put() x86/platform/iosf_mbi: Check return value of debugfs_create properly x86/platform/iosf_mbi: Move to dedicated folder x86/platform/intel/pmc_atom: Move the PMC-Atom code to arch/x86/platform/atom x86/platform/intel/pmc_atom: Add Cherrytrail PMC interface x86/platform/intel/pmc_atom: Supply register mappings via PMC object x86/platform/intel/pmc_atom: Print index of device in loop x86/platform/intel/pmc_atom: Export accessors to PMC registers
2015-09-01Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm changes from Ingo Molnar: "The biggest changes in this cycle were: - Revamp, simplify (and in some cases fix) Time Stamp Counter (TSC) primitives. (Andy Lutomirski) - Add new, comprehensible entry and exit handlers written in C. (Andy Lutomirski) - vm86 mode cleanups and fixes. (Brian Gerst) - 32-bit compat code cleanups. (Brian Gerst) The amount of simplification in low level assembly code is already palpable: arch/x86/entry/entry_32.S | 130 +---- arch/x86/entry/entry_64.S | 197 ++----- but more simplifications are planned. There's also the usual laudry mix of low level changes - see the changelog for details" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (83 commits) x86/asm: Drop repeated macro of X86_EFLAGS_AC definition x86/asm/msr: Make wrmsrl() a function x86/asm/delay: Introduce an MWAITX-based delay with a configurable timer x86/asm: Add MONITORX/MWAITX instruction support x86/traps: Weaken context tracking entry assertions x86/asm/tsc: Add rdtscll() merge helper selftests/x86: Add syscall_nt selftest selftests/x86: Disable sigreturn_64 x86/vdso: Emit a GNU hash x86/entry: Remove do_notify_resume(), syscall_trace_leave(), and their TIF masks x86/entry/32: Migrate to C exit path x86/entry/32: Remove 32-bit syscall audit optimizations x86/vm86: Rename vm86->v86flags and v86mask x86/vm86: Rename vm86->vm86_info to user_vm86 x86/vm86: Clean up vm86.h includes x86/vm86: Move the vm86 IRQ definitions to vm86.h x86/vm86: Use the normal pt_regs area for vm86 x86/vm86: Eliminate 'struct kernel_vm86_struct' x86/vm86: Move fields from 'struct kernel_vm86_struct' to 'struct vm86' x86/vm86: Move vm86 fields out of 'thread_struct' ...