5.4-stable review patch. If anyone has any objections, please let me know.
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From: Sean Anderson sean.anderson@linux.dev
[ Upstream commit 0199d2f2bd8cd97b310f7ed82a067247d7456029 ]
MSGF_LEG_MASK is laid out with INTA in bit 0, INTB in bit 1, INTC in bit 2, and INTD in bit 3. Hardware IRQ numbers start at 0, and we register PCI_NUM_INTX IRQs. So to enable INTA (aka hwirq 0) we should set bit 0. Remove the subtraction of one.
This bug would cause INTx interrupts not to be delivered, as enabling INTB would actually enable INTA, and enabling INTA wouldn't enable anything at all. It is likely that this got overlooked for so long since most PCIe hardware uses MSIs. This fixes the following UBSAN error:
UBSAN: shift-out-of-bounds in ../drivers/pci/controller/pcie-xilinx-nwl.c:389:11 shift exponent 18446744073709551615 is too large for 32-bit type 'int' CPU: 1 PID: 61 Comm: kworker/u10:1 Not tainted 6.6.20+ #268 Hardware name: xlnx,zynqmp (DT) Workqueue: events_unbound deferred_probe_work_func Call trace: dump_backtrace (arch/arm64/kernel/stacktrace.c:235) show_stack (arch/arm64/kernel/stacktrace.c:242) dump_stack_lvl (lib/dump_stack.c:107) dump_stack (lib/dump_stack.c:114) __ubsan_handle_shift_out_of_bounds (lib/ubsan.c:218 lib/ubsan.c:387) nwl_unmask_leg_irq (drivers/pci/controller/pcie-xilinx-nwl.c:389 (discriminator 1)) irq_enable (kernel/irq/internals.h:234 kernel/irq/chip.c:170 kernel/irq/chip.c:439 kernel/irq/chip.c:432 kernel/irq/chip.c:345) __irq_startup (kernel/irq/internals.h:239 kernel/irq/chip.c:180 kernel/irq/chip.c:250) irq_startup (kernel/irq/chip.c:270) __setup_irq (kernel/irq/manage.c:1800) request_threaded_irq (kernel/irq/manage.c:2206) pcie_pme_probe (include/linux/interrupt.h:168 drivers/pci/pcie/pme.c:348)
Fixes: 9a181e1093af ("PCI: xilinx-nwl: Modify IRQ chip for legacy interrupts") Link: https://lore.kernel.org/r/20240531161337.864994-3-sean.anderson@linux.dev Signed-off-by: Sean Anderson sean.anderson@linux.dev Signed-off-by: Bjorn Helgaas bhelgaas@google.com Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pci/controller/pcie-xilinx-nwl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/controller/pcie-xilinx-nwl.c b/drivers/pci/controller/pcie-xilinx-nwl.c index eb23bb28221a8..f08606f25e3c8 100644 --- a/drivers/pci/controller/pcie-xilinx-nwl.c +++ b/drivers/pci/controller/pcie-xilinx-nwl.c @@ -389,7 +389,7 @@ static void nwl_mask_leg_irq(struct irq_data *data) u32 mask; u32 val;
- mask = 1 << (data->hwirq - 1); + mask = 1 << data->hwirq; raw_spin_lock_irqsave(&pcie->leg_mask_lock, flags); val = nwl_bridge_readl(pcie, MSGF_LEG_MASK); nwl_bridge_writel(pcie, (val & (~mask)), MSGF_LEG_MASK); @@ -403,7 +403,7 @@ static void nwl_unmask_leg_irq(struct irq_data *data) u32 mask; u32 val;
- mask = 1 << (data->hwirq - 1); + mask = 1 << data->hwirq; raw_spin_lock_irqsave(&pcie->leg_mask_lock, flags); val = nwl_bridge_readl(pcie, MSGF_LEG_MASK); nwl_bridge_writel(pcie, (val | mask), MSGF_LEG_MASK);