kernel/drivers/xen, branch linux-rolling-stable

xen/acpi-processor: fix _CST detection using undersized evaluation buffer

2026-03-12T11:09:51Z

[ Upstream commit 8b57227d59a86fc06d4f09de08f98133680f2cae ] read_acpi_id() attempts to evaluate _CST using a stack buffer of sizeof(union acpi_object) (48 bytes), but _CST returns a nested Package of sub-Packages (one per C-state, each containing a register descriptor, type, latency, and power) requiring hundreds of bytes. The evaluation always fails with AE_BUFFER_OVERFLOW. On modern systems using FFH/MWAIT entry (where pblk is zero), this causes the function to return before setting the acpi_id_cst_present bit. In check_acpi_ids(), flags.power is then zero for all Phase 2 CPUs (physical CPUs beyond dom0's vCPU count), so push_cxx_to_hypervisor() is never called for them. On a system with dom0_max_vcpus=2 and 8 physical CPUs, only PCPUs 0-1 receive C-state data. PCPUs 2-7 are stuck in C0/C1 idle, unable to enter C2/C3. This costs measurable wall power (4W observed on an Intel Core Ultra 7 265K with Xen 4.20). The function never uses the _CST return value -- it only needs to know whether _CST exists. Replace the broken acpi_evaluate_object() call with acpi_has_method(), which correctly detects _CST presence using acpi_get_handle() without any buffer allocation. This brings C-state detection to parity with the P-state path, which already works correctly for Phase 2 CPUs. Fixes: 59a568029181 ("xen/acpi-processor: C and P-state driver that uploads said data to hypervisor.") Signed-off-by: David Thomson Reviewed-by: Jan Beulich Signed-off-by: Juergen Gross Message-ID: <20260224093707.19679-1-dt@linux-mail.net> Signed-off-by: Sasha Levin

xenbus: Use .freeze/.thaw to handle xenbus devices

2026-03-04T12:19:40Z

[ Upstream commit e08dd1ee49838750a514e83c0aa60cd12ba6ecbb ] The goal is to fix s2idle and S3 for Xen PV devices. A domain resuming from s3 or s2idle disconnects its PV devices during resume. The backends are not expecting this and do not reconnect. b3e96c0c7562 ("xen: use freeze/restore/thaw PM events for suspend/ resume/chkpt") changed xen_suspend()/do_suspend() from PMSG_SUSPEND/PMSG_RESUME to PMSG_FREEZE/PMSG_THAW/PMSG_RESTORE, but the suspend/resume callbacks remained. .freeze/restore are used with hiberation where Linux restarts in a new place in the future. .suspend/resume are useful for runtime power management for the duration of a boot. The current behavior of the callbacks works for an xl save/restore or live migration where the domain is restored/migrated to a new location and connecting to a not-already-connected backend. Change xenbus_pm_ops to use .freeze/thaw/restore and drop the .suspend/resume hook. This matches the use in drivers/xen/manage.c for save/restore and live migration. With .suspend/resume empty, PV devices are left connected during s2idle and s3, so PV devices are not changed and work after resume. Signed-off-by: Jason Andryuk Acked-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <20251119224731.61497-2-jason.andryuk@amd.com> Signed-off-by: Sasha Levin

Partial revert "x86/xen: fix balloon target initialization for PVH dom0"

2026-02-26T23:00:43Z

[ Upstream commit 0949c646d64697428ff6257d52efa5093566868d ] This partially reverts commit 87af633689ce16ddb166c80f32b120e50b1295de so the current memory target for PV guests is still fetched from start_info->nr_pages, which matches exactly what the toolstack sets the initial memory target to. Using get_num_physpages() is possible on PV also, but needs adjusting to take into account the ISA hole and the PFN at 0 not considered usable memory despite being populated, and hence would need extra adjustments. Instead of carrying those extra adjustments switch back to the previous code. That leaves Linux with a difference in how current memory target is obtained for HVM vs PV, but that's better than adding extra logic just for PV. However if switching to start_info->nr_pages for PV domains we need to differentiate between released pages (freed back to the hypervisor) as opposed to pages in the physmap which are not populated to start with. Introduce a new xen_unpopulated_pages to account for papges that have never been populated, and hence in the PV case don't need subtracting. Fixes: 87af633689ce ("x86/xen: fix balloon target initialization for PVH dom0") Reported-by: James Dingwall Signed-off-by: Roger Pau Monné Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <20260128110510.46425-2-roger.pau@citrix.com> Signed-off-by: Sasha Levin

xen/virtio: Don't use grant-dma-ops when running as Dom0

2026-02-26T23:00:42Z

[ Upstream commit dc8ea8714311e549ee93a2b0bdd5487d20bfadbf ] Dom0 inherit devices from the machine and is usually in PV mode. If we are running in a virtual that has virtio devices, these devices would be considered as using grants with Dom0 as backend, while being the said Dom0 itself, while we want to use these devices like regular PCI devices. Fix this by preventing grant-dma-ops from being used when running as Dom0 (initial domain). We still keep the device-tree logic as-is. Signed-off-by: Teddy Astie Fixes: 61367688f1fb0 ("xen/virtio: enable grant based virtio on x86") Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <6698564dd2270a9f7377b78ebfb20cb425cabbe8.1767720955.git.teddy.astie@vates.tech> Signed-off-by: Sasha Levin

Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2026-01-25T20:06:15Z

Pull SCSI fixes from James Bottomley: "Only one core change, the rest are drivers. The core change reorders some state operations in the error handler to try to prevent missed wake ups of the error handler (which can halt error processing and effectively freeze the entire system)" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: scsi: qla2xxx: Sanitize payload size to prevent member overflow scsi: target: iscsi: Fix use-after-free in iscsit_dec_session_usage_count() scsi: target: iscsi: Fix use-after-free in iscsit_dec_conn_usage_count() scsi: core: Wake up the error handler when final completions race against each other scsi: storvsc: Process unsupported MODE_SENSE_10 scsi: xen: scsiback: Fix potential memory leak in scsiback_remove()

scsi: xen: scsiback: Fix potential memory leak in scsiback_remove()

2026-01-12T02:35:49Z

Memory allocated for struct vscsiblk_info in scsiback_probe() is not freed in scsiback_remove() leading to potential memory leaks on remove, as well as in the scsiback_probe() error paths. Fix that by freeing it in scsiback_remove(). Cc: stable@vger.kernel.org Fixes: d9d660f6e562 ("xen-scsiback: Add Xen PV SCSI backend driver") Signed-off-by: Abdun Nihaal Reviewed-by: Juergen Gross Link: https://patch.msgid.link/20251223063012.119035-1-nihaal@cse.iitm.ac.in Signed-off-by: Martin K. Petersen

ACPI: PCI: IRQ: Fix INTx GSIs signedness

2026-01-05T18:06:40Z

In ACPI Global System Interrupts (GSIs) are described using a 32-bit value. ACPI/PCI legacy interrupts (INTx) parsing code treats GSIs as 'int', which poses issues if the GSI interrupt value is a 32-bit value with the MSB set (as required in some interrupt configurations - eg ARM64 GICv5 systems) because acpi_pci_link_allocate_irq() treats a negative gsi return value as a failed GSI allocation (and acpi_irq_get_penalty() would trigger an out-of-bounds array dereference if the 'irq' param is a negative value). Fix ACPI/PCI legacy INTx parsing by converting variables representing GSIs from 'int' to 'u32' bringing the code in line with the ACPI specification and fixing the current parsing issue. Signed-off-by: Lorenzo Pieralisi Reviewed-by: Bjorn Helgaas Link: https://patch.msgid.link/20260105101705.36703-1-lpieralisi@kernel.org Signed-off-by: Rafael J. Wysocki

Merge tag 'for-linus-6.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2025-12-06T18:49:19Z

Pull xen updates from Juergen Gross: "This round it contains only three small cleanup patches" * tag 'for-linus-6.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: drivers/xen: use min() instead of min_t() drivers/xen/xenbus: Replace deprecated strcpy in xenbus_transaction_end drivers/xen/xenbus: Simplify return statement in join()

Merge tag 'dma-mapping-6.19-2025-12-05' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux

2025-12-06T17:25:05Z

Pull dma-mapping updates from Marek Szyprowski: - More DMA mapping API refactoring to physical addresses as the primary interface instead of page+offset parameters. This time dma_map_ops callbacks are converted to physical addresses, what in turn results also in some simplification of architecture specific code (Leon Romanovsky and Jason Gunthorpe) - Clarify that dma_map_benchmark is not a kernel self-test, but standalone tool (Qinxin Xia) * tag 'dma-mapping-6.19-2025-12-05' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: dma-mapping: remove unused map_page callback xen: swiotlb: Convert mapping routine to rely on physical address x86: Use physical address for DMA mapping sparc: Use physical address DMA mapping powerpc: Convert to physical address DMA mapping parisc: Convert DMA map_page to map_phys interface MIPS/jazzdma: Provide physical address directly alpha: Convert mapping routine to rely on physical address dma-mapping: remove unused mapping resource callbacks xen: swiotlb: Switch to physical address mapping callbacks ARM: dma-mapping: Switch to physical address mapping callbacks ARM: dma-mapping: Reduce struct page exposure in arch_sync_dma*() dma-mapping: convert dummy ops to physical address mapping dma-mapping: prepare dma_map_ops to conversion to physical address tools/dma: move dma_map_benchmark from selftests to tools/dma

Merge tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

2025-12-06T01:29:04Z

Pull SoC driver updates from Arnd Bergmann: "This is the first half of the driver changes: - A treewide interface change to the "syscore" operations for power management, as a preparation for future Tegra specific changes - Reset controller updates with added drivers for LAN969x, eic770 and RZ/G3S SoCs - Protection of system controller registers on Renesas and Google SoCs, to prevent trivially triggering a system crash from e.g. debugfs access - soc_device identification updates on Nvidia, Exynos and Mediatek - debugfs support in the ST STM32 firewall driver - Minor updates for SoC drivers on AMD/Xilinx, Renesas, Allwinner, TI - Cleanups for memory controller support on Nvidia and Renesas" * tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (114 commits) memory: tegra186-emc: Fix missing put_bpmp Documentation: reset: Remove reset_controller_add_lookup() reset: fix BIT macro reference reset: rzg2l-usbphy-ctrl: Fix a NULL vs IS_ERR() bug in probe reset: th1520: Support reset controllers in more subsystems reset: th1520: Prepare for supporting multiple controllers dt-bindings: reset: thead,th1520-reset: Add controllers for more subsys dt-bindings: reset: thead,th1520-reset: Remove non-VO-subsystem resets reset: remove legacy reset lookup code clk: davinci: psc: drop unused reset lookup reset: rzg2l-usbphy-ctrl: Add support for RZ/G3S SoC reset: rzg2l-usbphy-ctrl: Add support for USB PWRRDY dt-bindings: reset: renesas,rzg2l-usbphy-ctrl: Document RZ/G3S support reset: eswin: Add eic7700 reset driver dt-bindings: reset: eswin: Documentation for eic7700 SoC reset: sparx5: add LAN969x support dt-bindings: reset: microchip: Add LAN969x support soc: rockchip: grf: Add select correct PWM implementation on RK3368 soc/tegra: pmc: Add USB wake events for Tegra234 amba: tegra-ahb: Fix device leak on SMMU enable ...