kernel/git/stable/linux-stable.git/drivers/xen, branch linux-6.17.y

xen/events: Update virq_to_irq on migration

2025-10-19T14:37:19+00:00

commit 3fcc8e146935415d69ffabb5df40ecf50e106131 upstream. VIRQs come in 3 flavors, per-VPU, per-domain, and global, and the VIRQs are tracked in per-cpu virq_to_irq arrays. Per-domain and global VIRQs must be bound on CPU 0, and bind_virq_to_irq() sets the per_cpu virq_to_irq at registration time Later, the interrupt can migrate, and info->cpu is updated. When calling __unbind_from_irq(), the per-cpu virq_to_irq is cleared for a different cpu. If bind_virq_to_irq() is called again with CPU 0, the stale irq is returned. There won't be any irq_info for the irq, so things break. Make xen_rebind_evtchn_to_cpu() update the per_cpu virq_to_irq mappings to keep them update to date with the current cpu. This ensures the correct virq_to_irq is cleared in __unbind_from_irq(). Fixes: e46cdb66c8fc ("xen: event channels") Cc: stable@vger.kernel.org Signed-off-by: Jason Andryuk Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <20250828003604.8949-4-jason.andryuk@amd.com> Signed-off-by: Greg Kroah-Hartman

xen/events: Return -EEXIST for bound VIRQs

2025-10-19T14:37:19+00:00

commit 07ce121d93a5e5fb2440a24da3dbf408fcee978e upstream. Change find_virq() to return -EEXIST when a VIRQ is bound to a different CPU than the one passed in. With that, remove the BUG_ON() from bind_virq_to_irq() to propogate the error upwards. Some VIRQs are per-cpu, but others are per-domain or global. Those must be bound to CPU0 and can then migrate elsewhere. The lookup for per-domain and global will probably fail when migrated off CPU 0, especially when the current CPU is tracked. This now returns -EEXIST instead of BUG_ON(). A second call to bind a per-domain or global VIRQ is not expected, but make it non-fatal to avoid trying to look up the irq, since we don't know which per_cpu(virq_to_irq) it will be in. Cc: stable@vger.kernel.org Signed-off-by: Jason Andryuk Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <20250828003604.8949-3-jason.andryuk@amd.com> Signed-off-by: Greg Kroah-Hartman

xen/manage: Fix suspend error path

2025-10-19T14:37:19+00:00

commit f770c3d858687252f1270265ba152d5c622e793f upstream. The device power management API has the following asymmetry: * dpm_suspend_start() does not clean up on failure (it requires a call to dpm_resume_end()) * dpm_suspend_end() does clean up on failure (it does not require a call to dpm_resume_start()) The asymmetry was introduced by commit d8f3de0d2412 ("Suspend-related patches for 2.6.27") in June 2008: It removed a call to device_resume() from device_suspend() (which was later renamed to dpm_suspend_start()). When Xen began using the device power management API in May 2008 with commit 0e91398f2a5d ("xen: implement save/restore"), the asymmetry did not yet exist. But since it was introduced, a call to dpm_resume_end() is missing in the error path of dpm_suspend_start(). Fix it. Fixes: d8f3de0d2412 ("Suspend-related patches for 2.6.27") Signed-off-by: Lukas Wunner Cc: stable@vger.kernel.org # v2.6.27 Reviewed-by: "Rafael J. Wysocki (Intel)" Signed-off-by: Juergen Gross Message-ID: <22453676d1ddcebbe81641bb68ddf587fee7e21e.1756990799.git.lukas@wunner.de> Signed-off-by: Greg Kroah-Hartman

xen/events: Cleanup find_virq() return codes

2025-10-19T14:37:19+00:00

commit 08df2d7dd4ab2db8a172d824cda7872d5eca460a upstream. rc is overwritten by the evtchn_status hypercall in each iteration, so the return value will be whatever the last iteration is. This could incorrectly return success even if the event channel was not found. Change to an explicit -ENOENT for an un-found virq and return 0 on a successful match. Fixes: 62cc5fc7b2e0 ("xen/pv-on-hvm kexec: rebind virqs to existing eventchannel ports") Cc: stable@vger.kernel.org Signed-off-by: Jason Andryuk Reviewed-by: Jan Beulich Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <20250828003604.8949-2-jason.andryuk@amd.com> Signed-off-by: Greg Kroah-Hartman

xen: take system_transition_mutex on suspend

2025-10-19T14:37:19+00:00

commit 9d52b0b41be5b932a0a929c10038f1bb04af4ca5 upstream. Xen's do_suspend() calls dpm_suspend_start() without taking required system_transition_mutex. Since 12ffc3b1513eb moved the pm_restrict_gfp_mask() call, not taking that mutex results in a WARN. Take the mutex in do_suspend(), and use mutex_trylock() to follow how enter_state() does this. Suggested-by: Jürgen Groß Fixes: 12ffc3b1513eb "PM: Restrict swap use to later in the suspend sequence" Link: https://lore.kernel.org/xen-devel/aKiBJeqsYx_4Top5@mail-itl/ Signed-off-by: Marek Marczykowski-Górecki Cc: stable@vger.kernel.org # v6.16+ Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <20250921162853.223116-1-marmarek@invisiblethingslab.com> Signed-off-by: Greg Kroah-Hartman

drivers/xen/xenbus: remove quirk for Xen 3.x

2025-08-20T13:47:43+00:00

The kernel is not supported to run as a Xen guest on Xen versions older than 4.0. Remove xen_strict_xenbus_quirk() which is testing the Xen version to be at least 4.0. Acked-by: Stefano Stabellini Reviewed-by: Jason Andryuk Signed-off-by: Juergen Gross Message-ID: <20250815074052.13792-1-jgross@suse.com>

xen/gntdev: remove struct gntdev_copy_batch from stack

2025-07-14T15:10:09+00:00

When compiling the kernel with LLVM, the following warning was issued: drivers/xen/gntdev.c:991: warning: stack frame size (1160) exceeds limit (1024) in function 'gntdev_ioctl' The main reason is struct gntdev_copy_batch which is located on the stack and has a size of nearly 1kb. For performance reasons it shouldn't by just dynamically allocated instead, so allocate a new instance when needed and instead of freeing it put it into a list of free structs anchored in struct gntdev_priv. Fixes: a4cdb556cae0 ("xen/gntdev: add ioctl for grant copy") Reported-by: Abinash Singh Reviewed-by: Stefano Stabellini Signed-off-by: Juergen Gross Message-ID: <20250703073259.17356-1-jgross@suse.com>

xen: fix UAF in dmabuf_exp_from_pages()

2025-07-14T08:12:07+00:00

[dma_buf_fd() fixes; no preferences regarding the tree it goes through - up to xen folks] As soon as we'd inserted a file reference into descriptor table, another thread could close it. That's fine for the case when all we are doing is returning that descriptor to userland (it's a race, but it's a userland race and there's nothing the kernel can do about it). However, if we follow fd_install() with any kind of access to objects that would be destroyed on close (be it the struct file itself or anything destroyed by its ->release()), we have a UAF. dma_buf_fd() is a combination of reserving a descriptor and fd_install(). gntdev dmabuf_exp_from_pages() calls it and then proceeds to access the objects destroyed on close - starting with gntdev_dmabuf itself. Fix that by doing reserving descriptor before anything else and do fd_install() only when everything had been set up. Fixes: a240d6e42e28 ("xen/gntdev: Implement dma-buf export functionality") Signed-off-by: Al Viro Acked-by: Juergen Gross Message-ID: <20250712050916.GY1880847@ZenIV> Signed-off-by: Juergen Gross

xen: Remove some deadcode (x)

2025-07-14T07:55:52+00:00

Remove three uncalled functions: xenbus_mkdir() was added in 2007 by commit 4bac07c993d0 ("xen: add the Xenbus sysfs and virtual device hotplug driver") but has remained unused. xen_get_runstate_snapshot() last use was removed in 2016 by commit 6ba286ad8457 ("xen: support runqueue steal time on xen") which replaces the use by the _cpu version. xen_resume_notifier_unregister() last use was removed in 2017 by commit 1914f0cd203c ("xen/acpi: upload PM state from init-domain to Xen") Remove them. Signed-off-by: "Dr. David Alan Gilbert" Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <20250713132625.164728-1-linux@treblig.org>

xen-pciback: Replace scnprintf() with sysfs_emit_at()

2025-07-14T07:35:42+00:00

This is the third revision (v3) of this patch series. No changes since v2—only adding Reviewed-by lines. Reviewed-by: Juergen Gross Signed-off-by: Ryan Chung Signed-off-by: Juergen Gross Message-ID: <20250708001444.86155-1-seokwoo.chung130@gmail.com>