irqchip/riscv-imsic: Revert "Remove redundant irq_data lookups"

Commit c475c0b71314("irqchip/riscv-imsic: Remove redundant irq_data
lookups") leads to a NULL pointer deference in imsic_msi_update_msg():

 virtio_blk virtio1: 8/0/0 default/read/poll queues
 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
 Current kworker/u32:2 pgtable: 4K pagesize, 48-bit VAs, pgdp=0x0000000081c33000
 [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
 CPU: 5 UID: 0 PID: 75 Comm: kworker/u32:2 Not tainted 6.19.0-rc4-next-20260109 #1 NONE
 epc : 0x0
  ra : imsic_irq_set_affinity+0x110/0x130

The irq_data argument of imsic_irq_set_affinity() is associated with the
imsic domain and not with the top-level MSI domain. As a consequence the
code dereferences the wrong interrupt chip, which has the
irq_write_msi_msg() callback not populated.

Signed-off-by: Luo Haiyang <luo.haiyang@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260113111930821RrC26avITHWSFCN0bYbgI@zte.com.cn

diff --git a/drivers/irqchip/irq-riscv-imsic-platform.c b/drivers/irqchip/irq-riscv-imsic-platform.c
index 7228a33f6c37fd316ddb4d4250e21569075c90c0..643c8e45961173399476ed17ae1b97c3bafca233 100644 (file)
--- a/drivers/irqchip/irq-riscv-imsic-platform.c
+++ b/drivers/irqchip/irq-riscv-imsic-platform.c
@@ -158,11 +158,11 @@ static int imsic_irq_set_affinity(struct irq_data *d, const struct cpumask *mask
                tmp_vec.local_id = new_vec->local_id;
 
                /* Point device to the temporary vector */
-               imsic_msi_update_msg(d, &tmp_vec);
+               imsic_msi_update_msg(irq_get_irq_data(d->irq), &tmp_vec);
        }
 
        /* Point device to the new vector */
-       imsic_msi_update_msg(d, new_vec);
+       imsic_msi_update_msg(irq_get_irq_data(d->irq), new_vec);
 
        /* Update irq descriptors with the new vector */
        d->chip_data = new_vec;