linux.git/drivers/xen/events, branch for-next Linux kernel source tree xen/events: Switch to irq_get_nr_irqs() 2024-10-16T19:56:59+00:00 Bart Van Assche bvanassche@acm.org 2024-10-15T19:09:50+00:00 3e48fa2ecf4de8baf8a368987f8ea8ffb64ac7af Use the irq_get_nr_irqs() function instead of the global variable 'nr_irqs'. Prepare for changing 'nr_irqs' from an exported global variable into a variable with file scope. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20241015190953.1266194-20-bvanassche@acm.org 
Use the irq_get_nr_irqs() function instead of the global variable
'nr_irqs'. Prepare for changing 'nr_irqs' from an exported global
variable into a variable with file scope.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20241015190953.1266194-20-bvanassche@acm.org
Merge tag 'for-linus-6.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip 2024-03-19T15:48:09+00:00 Linus Torvalds torvalds@linux-foundation.org 2024-03-19T15:48:09+00:00 0815d5cc7dfb4a2c6d02a6eb86974ab3992b803d Pull xen updates from Juergen Gross: - Xen event channel handling fix for a regression with a rare kernel config and some added hardening - better support of running Xen dom0 in PVH mode - a cleanup for the xen grant-dma-iommu driver * tag 'for-linus-6.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/events: increment refcnt only if event channel is refcounted xen/evtchn: avoid WARN() when unbinding an event channel x86/xen: attempt to inflate the memory balloon on PVH xen/grant-dma-iommu: Convert to platform remove callback returning void 
Pull xen updates from Juergen Gross:

 - Xen event channel handling fix for a regression with a rare kernel
   config and some added hardening

 - better support of running Xen dom0 in PVH mode

 - a cleanup for the xen grant-dma-iommu driver

* tag 'for-linus-6.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/events: increment refcnt only if event channel is refcounted
  xen/evtchn: avoid WARN() when unbinding an event channel
  x86/xen: attempt to inflate the memory balloon on PVH
  xen/grant-dma-iommu: Convert to platform remove callback returning void
xen/events: increment refcnt only if event channel is refcounted 2024-03-17T17:57:12+00:00 Juergen Gross jgross@suse.com 2024-03-13T07:14:09+00:00 d277f9d82802223f242cd9b60c988cfdda1d6be0 In bind_evtchn_to_irq_chip() don't increment the refcnt of the event channel blindly. In case the event channel is NOT refcounted, issue a warning instead. Add an additional safety net by doing the refcnt increment only if the caller has specified IRQF_SHARED in the irqflags parameter. Fixes: 9e90e58c11b7 ("xen: evtchn: Allow shared registration of IRQ handers") Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Link: https://lore.kernel.org/r/20240313071409.25913-3-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com> 
In bind_evtchn_to_irq_chip() don't increment the refcnt of the event
channel blindly. In case the event channel is NOT refcounted, issue a
warning instead.

Add an additional safety net by doing the refcnt increment only if the
caller has specified IRQF_SHARED in the irqflags parameter.

Fixes: 9e90e58c11b7 ("xen: evtchn: Allow shared registration of IRQ handers")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Link: https://lore.kernel.org/r/20240313071409.25913-3-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Merge tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2024-03-11T23:00:17+00:00 Linus Torvalds torvalds@linux-foundation.org 2024-03-11T23:00:17+00:00 720c857907530e6cdc86c9bc1102ea6b372fbfb6 Pull x86 FRED support from Thomas Gleixner: "Support for x86 Fast Return and Event Delivery (FRED). FRED is a replacement for IDT event delivery on x86 and addresses most of the technical nightmares which IDT exposes: 1) Exception cause registers like CR2 need to be manually preserved in nested exception scenarios. 2) Hardware interrupt stack switching is suboptimal for nested exceptions as the interrupt stack mechanism rewinds the stack on each entry which requires a massive effort in the low level entry of #NMI code to handle this. 3) No hardware distinction between entry from kernel or from user which makes establishing kernel context more complex than it needs to be especially for unconditionally nestable exceptions like NMI. 4) NMI nesting caused by IRET unconditionally reenabling NMIs, which is a problem when the perf NMI takes a fault when collecting a stack trace. 5) Partial restore of ESP when returning to a 16-bit segment 6) Limitation of the vector space which can cause vector exhaustion on large systems. 7) Inability to differentiate NMI sources FRED addresses these shortcomings by: 1) An extended exception stack frame which the CPU uses to save exception cause registers. This ensures that the meta information for each exception is preserved on stack and avoids the extra complexity of preserving it in software. 2) Hardware interrupt stack switching is non-rewinding if a nested exception uses the currently interrupt stack. 3) The entry points for kernel and user context are separate and GS BASE handling which is required to establish kernel context for per CPU variable access is done in hardware. 4) NMIs are now nesting protected. They are only reenabled on the return from NMI. 5) FRED guarantees full restore of ESP 6) FRED does not put a limitation on the vector space by design because it uses a central entry points for kernel and user space and the CPUstores the entry type (exception, trap, interrupt, syscall) on the entry stack along with the vector number. The entry code has to demultiplex this information, but this removes the vector space restriction. The first hardware implementations will still have the current restricted vector space because lifting this limitation requires further changes to the local APIC. 7) FRED stores the vector number and meta information on stack which allows having more than one NMI vector in future hardware when the required local APIC changes are in place. The series implements the initial FRED support by: - Reworking the existing entry and IDT handling infrastructure to accomodate for the alternative entry mechanism. - Expanding the stack frame to accomodate for the extra 16 bytes FRED requires to store context and meta information - Providing FRED specific C entry points for events which have information pushed to the extended stack frame, e.g. #PF and #DB. - Providing FRED specific C entry points for #NMI and #MCE - Implementing the FRED specific ASM entry points and the C code to demultiplex the events - Providing detection and initialization mechanisms and the necessary tweaks in context switching, GS BASE handling etc. The FRED integration aims for maximum code reuse vs the existing IDT implementation to the extent possible and the deviation in hot paths like context switching are handled with alternatives to minimalize the impact. The low level entry and exit paths are seperate due to the extended stack frame and the hardware based GS BASE swichting and therefore have no impact on IDT based systems. It has been extensively tested on existing systems and on the FRED simulation and as of now there are no outstanding problems" * tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) x86/fred: Fix init_task thread stack pointer initialization MAINTAINERS: Add a maintainer entry for FRED x86/fred: Fix a build warning with allmodconfig due to 'inline' failing to inline properly x86/fred: Invoke FRED initialization code to enable FRED x86/fred: Add FRED initialization functions x86/syscall: Split IDT syscall setup code into idt_syscall_init() KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled x86/traps: Add sysvec_install() to install a system interrupt handler x86/fred: FRED entry/exit and dispatch code x86/fred: Add a machine check entry stub for FRED x86/fred: Add a NMI entry stub for FRED x86/fred: Add a debug fault entry stub for FRED x86/idtentry: Incorporate definitions/declarations of the FRED entries x86/fred: Make exc_page_fault() work for FRED x86/fred: Allow single-step trap and NMI when starting a new task x86/fred: No ESPFIX needed when FRED is enabled ... 
Pull x86 FRED support from Thomas Gleixner:
 "Support for x86 Fast Return and Event Delivery (FRED).

  FRED is a replacement for IDT event delivery on x86 and addresses most
  of the technical nightmares which IDT exposes:

   1) Exception cause registers like CR2 need to be manually preserved
      in nested exception scenarios.

   2) Hardware interrupt stack switching is suboptimal for nested
      exceptions as the interrupt stack mechanism rewinds the stack on
      each entry which requires a massive effort in the low level entry
      of #NMI code to handle this.

   3) No hardware distinction between entry from kernel or from user
      which makes establishing kernel context more complex than it needs
      to be especially for unconditionally nestable exceptions like NMI.

   4) NMI nesting caused by IRET unconditionally reenabling NMIs, which
      is a problem when the perf NMI takes a fault when collecting a
      stack trace.

   5) Partial restore of ESP when returning to a 16-bit segment

   6) Limitation of the vector space which can cause vector exhaustion
      on large systems.

   7) Inability to differentiate NMI sources

  FRED addresses these shortcomings by:

   1) An extended exception stack frame which the CPU uses to save
      exception cause registers. This ensures that the meta information
      for each exception is preserved on stack and avoids the extra
      complexity of preserving it in software.

   2) Hardware interrupt stack switching is non-rewinding if a nested
      exception uses the currently interrupt stack.

   3) The entry points for kernel and user context are separate and GS
      BASE handling which is required to establish kernel context for
      per CPU variable access is done in hardware.

   4) NMIs are now nesting protected. They are only reenabled on the
      return from NMI.

   5) FRED guarantees full restore of ESP

   6) FRED does not put a limitation on the vector space by design
      because it uses a central entry points for kernel and user space
      and the CPUstores the entry type (exception, trap, interrupt,
      syscall) on the entry stack along with the vector number. The
      entry code has to demultiplex this information, but this removes
      the vector space restriction.

      The first hardware implementations will still have the current
      restricted vector space because lifting this limitation requires
      further changes to the local APIC.

   7) FRED stores the vector number and meta information on stack which
      allows having more than one NMI vector in future hardware when the
      required local APIC changes are in place.

  The series implements the initial FRED support by:

   - Reworking the existing entry and IDT handling infrastructure to
     accomodate for the alternative entry mechanism.

   - Expanding the stack frame to accomodate for the extra 16 bytes FRED
     requires to store context and meta information

   - Providing FRED specific C entry points for events which have
     information pushed to the extended stack frame, e.g. #PF and #DB.

   - Providing FRED specific C entry points for #NMI and #MCE

   - Implementing the FRED specific ASM entry points and the C code to
     demultiplex the events

   - Providing detection and initialization mechanisms and the necessary
     tweaks in context switching, GS BASE handling etc.

  The FRED integration aims for maximum code reuse vs the existing IDT
  implementation to the extent possible and the deviation in hot paths
  like context switching are handled with alternatives to minimalize the
  impact. The low level entry and exit paths are seperate due to the
  extended stack frame and the hardware based GS BASE swichting and
  therefore have no impact on IDT based systems.

  It has been extensively tested on existing systems and on the FRED
  simulation and as of now there are no outstanding problems"

* tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  x86/fred: Fix init_task thread stack pointer initialization
  MAINTAINERS: Add a maintainer entry for FRED
  x86/fred: Fix a build warning with allmodconfig due to 'inline' failing to inline properly
  x86/fred: Invoke FRED initialization code to enable FRED
  x86/fred: Add FRED initialization functions
  x86/syscall: Split IDT syscall setup code into idt_syscall_init()
  KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling
  x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI
  x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code
  x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user
  x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled
  x86/traps: Add sysvec_install() to install a system interrupt handler
  x86/fred: FRED entry/exit and dispatch code
  x86/fred: Add a machine check entry stub for FRED
  x86/fred: Add a NMI entry stub for FRED
  x86/fred: Add a debug fault entry stub for FRED
  x86/idtentry: Incorporate definitions/declarations of the FRED entries
  x86/fred: Make exc_page_fault() work for FRED
  x86/fred: Allow single-step trap and NMI when starting a new task
  x86/fred: No ESPFIX needed when FRED is enabled
  ...
xen/events: close evtchn after mapping cleanup 2024-02-13T09:12:47+00:00 Maximilian Heyne mheyne@amazon.de 2024-01-24T16:31:28+00:00 fa765c4b4aed2d64266b694520ecb025c862c5a9 shutdown_pirq and startup_pirq are not taking the irq_mapping_update_lock because they can't due to lock inversion. Both are called with the irq_desc->lock being taking. The lock order, however, is first irq_mapping_update_lock and then irq_desc->lock. This opens multiple races: - shutdown_pirq can be interrupted by a function that allocates an event channel: CPU0 CPU1 shutdown_pirq { xen_evtchn_close(e) __startup_pirq { EVTCHNOP_bind_pirq -> returns just freed evtchn e set_evtchn_to_irq(e, irq) } xen_irq_info_cleanup() { set_evtchn_to_irq(e, -1) } } Assume here event channel e refers here to the same event channel number. After this race the evtchn_to_irq mapping for e is invalid (-1). - __startup_pirq races with __unbind_from_irq in a similar way. Because __startup_pirq doesn't take irq_mapping_update_lock it can grab the evtchn that __unbind_from_irq is currently freeing and cleaning up. In this case even though the event channel is allocated, its mapping can be unset in evtchn_to_irq. The fix is to first cleanup the mappings and then close the event channel. In this way, when an event channel gets allocated it's potential previous evtchn_to_irq mappings are guaranteed to be unset already. This is also the reverse order of the allocation where first the event channel is allocated and then the mappings are setup. On a 5.10 kernel prior to commit 3fcdaf3d7634 ("xen/events: modify internal [un]bind interfaces"), we hit a BUG like the following during probing of NVMe devices. The issue is that during nvme_setup_io_queues, pci_free_irq is called for every device which results in a call to shutdown_pirq. With many nvme devices it's therefore likely to hit this race during boot because there will be multiple calls to shutdown_pirq and startup_pirq are running potentially in parallel. ------------[ cut here ]------------ blkfront: xvda: barrier or flush: disabled; persistent grants: enabled; indirect descriptors: enabled; bounce buffer: enabled kernel BUG at drivers/xen/events/events_base.c:499! invalid opcode: 0000 [#1] SMP PTI CPU: 44 PID: 375 Comm: kworker/u257:23 Not tainted 5.10.201-191.748.amzn2.x86_64 #1 Hardware name: Xen HVM domU, BIOS 4.11.amazon 08/24/2006 Workqueue: nvme-reset-wq nvme_reset_work RIP: 0010:bind_evtchn_to_cpu+0xdf/0xf0 Code: 5d 41 5e c3 cc cc cc cc 44 89 f7 e8 2b 55 ad ff 49 89 c5 48 85 c0 0f 84 64 ff ff ff 4c 8b 68 30 41 83 fe ff 0f 85 60 ff ff ff <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 0f 1f 44 00 00 RSP: 0000:ffffc9000d533b08 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000006 RDX: 0000000000000028 RSI: 00000000ffffffff RDI: 00000000ffffffff RBP: ffff888107419680 R08: 0000000000000000 R09: ffffffff82d72b00 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000001ed R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff88bc8b500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000002610001 CR4: 00000000001706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? show_trace_log_lvl+0x1c1/0x2d9 ? show_trace_log_lvl+0x1c1/0x2d9 ? set_affinity_irq+0xdc/0x1c0 ? __die_body.cold+0x8/0xd ? die+0x2b/0x50 ? do_trap+0x90/0x110 ? bind_evtchn_to_cpu+0xdf/0xf0 ? do_error_trap+0x65/0x80 ? bind_evtchn_to_cpu+0xdf/0xf0 ? exc_invalid_op+0x4e/0x70 ? bind_evtchn_to_cpu+0xdf/0xf0 ? asm_exc_invalid_op+0x12/0x20 ? bind_evtchn_to_cpu+0xdf/0xf0 ? bind_evtchn_to_cpu+0xc5/0xf0 set_affinity_irq+0xdc/0x1c0 irq_do_set_affinity+0x1d7/0x1f0 irq_setup_affinity+0xd6/0x1a0 irq_startup+0x8a/0xf0 __setup_irq+0x639/0x6d0 ? nvme_suspend+0x150/0x150 request_threaded_irq+0x10c/0x180 ? nvme_suspend+0x150/0x150 pci_request_irq+0xa8/0xf0 ? __blk_mq_free_request+0x74/0xa0 queue_request_irq+0x6f/0x80 nvme_create_queue+0x1af/0x200 nvme_create_io_queues+0xbd/0xf0 nvme_setup_io_queues+0x246/0x320 ? nvme_irq_check+0x30/0x30 nvme_reset_work+0x1c8/0x400 process_one_work+0x1b0/0x350 worker_thread+0x49/0x310 ? process_one_work+0x350/0x350 kthread+0x11b/0x140 ? __kthread_bind_mask+0x60/0x60 ret_from_fork+0x22/0x30 Modules linked in: ---[ end trace a11715de1eee1873 ]--- Fixes: d46a78b05c0e ("xen: implement pirq type event channels") Cc: stable@vger.kernel.org Co-debugged-by: Andrew Panyakin <apanyaki@amazon.com> Signed-off-by: Maximilian Heyne <mheyne@amazon.de> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20240124163130.31324-1-mheyne@amazon.de Signed-off-by: Juergen Gross <jgross@suse.com> 
shutdown_pirq and startup_pirq are not taking the
irq_mapping_update_lock because they can't due to lock inversion. Both
are called with the irq_desc->lock being taking. The lock order,
however, is first irq_mapping_update_lock and then irq_desc->lock.

This opens multiple races:
- shutdown_pirq can be interrupted by a function that allocates an event
  channel:

  CPU0                        CPU1
  shutdown_pirq {
    xen_evtchn_close(e)
                              __startup_pirq {
                                EVTCHNOP_bind_pirq
                                  -> returns just freed evtchn e
                                set_evtchn_to_irq(e, irq)
                              }
    xen_irq_info_cleanup() {
      set_evtchn_to_irq(e, -1)
    }
  }

  Assume here event channel e refers here to the same event channel
  number.
  After this race the evtchn_to_irq mapping for e is invalid (-1).

- __startup_pirq races with __unbind_from_irq in a similar way. Because
  __startup_pirq doesn't take irq_mapping_update_lock it can grab the
  evtchn that __unbind_from_irq is currently freeing and cleaning up. In
  this case even though the event channel is allocated, its mapping can
  be unset in evtchn_to_irq.

The fix is to first cleanup the mappings and then close the event
channel. In this way, when an event channel gets allocated it's
potential previous evtchn_to_irq mappings are guaranteed to be unset already.
This is also the reverse order of the allocation where first the event
channel is allocated and then the mappings are setup.

On a 5.10 kernel prior to commit 3fcdaf3d7634 ("xen/events: modify internal
[un]bind interfaces"), we hit a BUG like the following during probing of NVMe
devices. The issue is that during nvme_setup_io_queues, pci_free_irq
is called for every device which results in a call to shutdown_pirq.
With many nvme devices it's therefore likely to hit this race during
boot because there will be multiple calls to shutdown_pirq and
startup_pirq are running potentially in parallel.

  ------------[ cut here ]------------
  blkfront: xvda: barrier or flush: disabled; persistent grants: enabled; indirect descriptors: enabled; bounce buffer: enabled
  kernel BUG at drivers/xen/events/events_base.c:499!
  invalid opcode: 0000 [#1] SMP PTI
  CPU: 44 PID: 375 Comm: kworker/u257:23 Not tainted 5.10.201-191.748.amzn2.x86_64 #1
  Hardware name: Xen HVM domU, BIOS 4.11.amazon 08/24/2006
  Workqueue: nvme-reset-wq nvme_reset_work
  RIP: 0010:bind_evtchn_to_cpu+0xdf/0xf0
  Code: 5d 41 5e c3 cc cc cc cc 44 89 f7 e8 2b 55 ad ff 49 89 c5 48 85 c0 0f 84 64 ff ff ff 4c 8b 68 30 41 83 fe ff 0f 85 60 ff ff ff <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 0f 1f 44 00 00
  RSP: 0000:ffffc9000d533b08 EFLAGS: 00010046
  RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000006
  RDX: 0000000000000028 RSI: 00000000ffffffff RDI: 00000000ffffffff
  RBP: ffff888107419680 R08: 0000000000000000 R09: ffffffff82d72b00
  R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000001ed
  R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000002
  FS:  0000000000000000(0000) GS:ffff88bc8b500000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 0000000002610001 CR4: 00000000001706e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   ? show_trace_log_lvl+0x1c1/0x2d9
   ? show_trace_log_lvl+0x1c1/0x2d9
   ? set_affinity_irq+0xdc/0x1c0
   ? __die_body.cold+0x8/0xd
   ? die+0x2b/0x50
   ? do_trap+0x90/0x110
   ? bind_evtchn_to_cpu+0xdf/0xf0
   ? do_error_trap+0x65/0x80
   ? bind_evtchn_to_cpu+0xdf/0xf0
   ? exc_invalid_op+0x4e/0x70
   ? bind_evtchn_to_cpu+0xdf/0xf0
   ? asm_exc_invalid_op+0x12/0x20
   ? bind_evtchn_to_cpu+0xdf/0xf0
   ? bind_evtchn_to_cpu+0xc5/0xf0
   set_affinity_irq+0xdc/0x1c0
   irq_do_set_affinity+0x1d7/0x1f0
   irq_setup_affinity+0xd6/0x1a0
   irq_startup+0x8a/0xf0
   __setup_irq+0x639/0x6d0
   ? nvme_suspend+0x150/0x150
   request_threaded_irq+0x10c/0x180
   ? nvme_suspend+0x150/0x150
   pci_request_irq+0xa8/0xf0
   ? __blk_mq_free_request+0x74/0xa0
   queue_request_irq+0x6f/0x80
   nvme_create_queue+0x1af/0x200
   nvme_create_io_queues+0xbd/0xf0
   nvme_setup_io_queues+0x246/0x320
   ? nvme_irq_check+0x30/0x30
   nvme_reset_work+0x1c8/0x400
   process_one_work+0x1b0/0x350
   worker_thread+0x49/0x310
   ? process_one_work+0x350/0x350
   kthread+0x11b/0x140
   ? __kthread_bind_mask+0x60/0x60
   ret_from_fork+0x22/0x30
  Modules linked in:
  ---[ end trace a11715de1eee1873 ]---

Fixes: d46a78b05c0e ("xen: implement pirq type event channels")
Cc: stable@vger.kernel.org
Co-debugged-by: Andrew Panyakin <apanyaki@amazon.com>
Signed-off-by: Maximilian Heyne <mheyne@amazon.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20240124163130.31324-1-mheyne@amazon.de
Signed-off-by: Juergen Gross <jgross@suse.com>
x86/traps: Add sysvec_install() to install a system interrupt handler 2024-01-31T21:02:36+00:00 Xin Li xin3.li@intel.com 2023-12-05T10:50:16+00:00 8f4a29b0e8a40d865040800684d7ff4141c1394f Add sysvec_install() to install a system interrupt handler into the IDT or the FRED system interrupt handler table. Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-28-xin3.li@intel.com 
Add sysvec_install() to install a system interrupt handler into the IDT
or the FRED system interrupt handler table.

Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Shan Kang <shan.kang@intel.com>
Link: https://lore.kernel.org/r/20231205105030.8698-28-xin3.li@intel.com
xen/events: fix error code in xen_bind_pirq_msi_to_irq() 2023-11-28T11:48:27+00:00 Dan Carpenter dan.carpenter@linaro.org 2023-11-28T06:52:41+00:00 7f3da4b698bcc21a6df0e7f114af71d53a3e26ac Return -ENOMEM if xen_irq_init() fails. currently the code returns an uninitialized variable or zero. Fixes: 5dd9ad32d775 ("xen/events: drop xen_allocate_irqs_dynamic()") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: Juergen Gross <jgross@ssue.com> Link: https://lore.kernel.org/r/3b9ab040-a92e-4e35-b687-3a95890a9ace@moroto.mountain Signed-off-by: Juergen Gross <jgross@suse.com> 
Return -ENOMEM if xen_irq_init() fails.  currently the code returns an
uninitialized variable or zero.

Fixes: 5dd9ad32d775 ("xen/events: drop xen_allocate_irqs_dynamic()")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Juergen Gross <jgross@ssue.com>
Link: https://lore.kernel.org/r/3b9ab040-a92e-4e35-b687-3a95890a9ace@moroto.mountain
Signed-off-by: Juergen Gross <jgross@suse.com>
xen/events: remove some info_for_irq() calls in pirq handling 2023-11-15T08:51:51+00:00 Juergen Gross jgross@suse.com 2023-09-28T09:25:32+00:00 cee96422e863f0b0e9d3d0c2d617271ef2255858 Instead of the IRQ number user the struct irq_info pointer as parameter in the internal pirq related functions. This allows to drop some calls of info_for_irq(). Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Signed-off-by: Juergen Gross <jgross@suse.com> 
Instead of the IRQ number user the struct irq_info pointer as parameter
in the internal pirq related functions. This allows to drop some calls
of info_for_irq().

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
xen/events: modify internal [un]bind interfaces 2023-11-15T08:29:39+00:00 Juergen Gross jgross@suse.com 2023-09-28T07:09:52+00:00 3fcdaf3d7634338c3f5cbfa7451eb0b6b0024844 Modify the internal bind- and unbind-interfaces to take a struct irq_info parameter. When allocating a new IRQ pass the pointer from the allocating function further up. This will reduce the number of info_for_irq() calls and make the code more efficient. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Signed-off-by: Juergen Gross <jgross@suse.com> 
Modify the internal bind- and unbind-interfaces to take a struct
irq_info parameter. When allocating a new IRQ pass the pointer from
the allocating function further up.

This will reduce the number of info_for_irq() calls and make the code
more efficient.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
xen/events: drop xen_allocate_irqs_dynamic() 2023-11-15T08:02:59+00:00 Juergen Gross jgross@suse.com 2023-09-27T08:29:02+00:00 5dd9ad32d7758b1a76742f394acf0eb3ac8a636a Instead of having a common function for allocating a single IRQ or a consecutive number of IRQs, split up the functionality into the callers of xen_allocate_irqs_dynamic(). This allows to handle any allocation error in xen_irq_init() gracefully instead of panicing the system. Let xen_irq_init() return the irq_info pointer or NULL in case of an allocation error. Additionally set the IRQ into irq_info already at allocation time, as otherwise the IRQ would be '0' (which is a valid IRQ number) until being set. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Signed-off-by: Juergen Gross <jgross@suse.com> 
Instead of having a common function for allocating a single IRQ or a
consecutive number of IRQs, split up the functionality into the callers
of xen_allocate_irqs_dynamic().

This allows to handle any allocation error in xen_irq_init() gracefully
instead of panicing the system. Let xen_irq_init() return the irq_info
pointer or NULL in case of an allocation error.

Additionally set the IRQ into irq_info already at allocation time, as
otherwise the IRQ would be '0' (which is a valid IRQ number) until
being set.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Juergen Gross <jgross@suse.com>