Nilay Shroff 6771c54728 powerpc/xive: fix kmemleak caused by incorrect chip_data lookup
The kmemleak reports the following memory leak:

Unreferenced object 0xc0000002a7fbc640 (size 64):
  comm "kworker/8:1", pid 540, jiffies 4294937872
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 00 00 09 04 00 04 00 00  ................
    00 00 a7 81 00 00 0a c0 00 00 08 04 00 04 00 00  ................
  backtrace (crc 177d48f6):
    __kmalloc_cache_noprof+0x520/0x730
    xive_irq_alloc_data.constprop.0+0x40/0xe0
    xive_irq_domain_alloc+0xd0/0x1b0
    irq_domain_alloc_irqs_parent+0x44/0x6c
    pseries_irq_domain_alloc+0x1cc/0x354
    irq_domain_alloc_irqs_parent+0x44/0x6c
    msi_domain_alloc+0xb0/0x220
    irq_domain_alloc_irqs_locked+0x138/0x4d0
    __irq_domain_alloc_irqs+0x8c/0xfc
    __msi_domain_alloc_irqs+0x214/0x4d8
    msi_domain_alloc_irqs_all_locked+0x70/0xf8
    pci_msi_setup_msi_irqs+0x60/0x78
    __pci_enable_msix_range+0x54c/0x98c
    pci_alloc_irq_vectors_affinity+0x16c/0x1d4
    nvme_pci_enable+0xac/0x9c0 [nvme]
    nvme_probe+0x340/0x764 [nvme]

This occurs when allocating MSI-X vectors for an NVMe device. During
allocation the XIVE code creates a struct xive_irq_data and stores it
in irq_data->chip_data.

When the MSI-X irqdomain is later freed, xive_irq_free_data() is
responsible for retrieving this structure and freeing it. However,
after commit cc0cc23bab ("powerpc/xive: Untangle xive from child
interrupt controller drivers"), xive_irq_free_data() retrieves the
chip_data using irq_get_chip_data(), which looks up the data through
the child domain.

This is incorrect because the XIVE-specific irq data is associated with
the XIVE (parent) domain. As a result the lookup fails and the allocated
struct xive_irq_data is never freed, leading to the kmemleak report
shown above.

Fix this by retrieving the irq_data from the correct domain using
irq_domain_get_irq_data() and then accessing the chip_data via
irq_data_get_irq_chip_data().

Cc: stable@vger.kernel.org
Fixes: cc0cc23bab ("powerpc/xive: Untangle xive from child interrupt controller drivers")
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260311134336.326996-1-nilay@linux.ibm.com
2026-03-30 16:15:57 +05:30
2026-01-26 19:07:09 -08:00
2022-09-28 09:02:20 +02:00
2025-02-19 14:53:27 -07:00
2026-03-15 13:52:05 -07:00

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