CVE-2025-21821

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> fbdev: omap: use threaded IRQ for LCD DMA<br /> <br /> When using touchscreen and framebuffer, Nokia 770 crashes easily with:<br /> <br /> BUG: scheduling while atomic: irq/144-ads7846/82/0x00010000<br /> Modules linked in: usb_f_ecm g_ether usb_f_rndis u_ether libcomposite configfs omap_udc ohci_omap ohci_hcd<br /> CPU: 0 UID: 0 PID: 82 Comm: irq/144-ads7846 Not tainted 6.12.7-770 #2<br /> Hardware name: Nokia 770<br /> Call trace:<br /> unwind_backtrace from show_stack+0x10/0x14<br /> show_stack from dump_stack_lvl+0x54/0x5c<br /> dump_stack_lvl from __schedule_bug+0x50/0x70<br /> __schedule_bug from __schedule+0x4d4/0x5bc<br /> __schedule from schedule+0x34/0xa0<br /> schedule from schedule_preempt_disabled+0xc/0x10<br /> schedule_preempt_disabled from __mutex_lock.constprop.0+0x218/0x3b4<br /> __mutex_lock.constprop.0 from clk_prepare_lock+0x38/0xe4<br /> clk_prepare_lock from clk_set_rate+0x18/0x154<br /> clk_set_rate from sossi_read_data+0x4c/0x168<br /> sossi_read_data from hwa742_read_reg+0x5c/0x8c<br /> hwa742_read_reg from send_frame_handler+0xfc/0x300<br /> send_frame_handler from process_pending_requests+0x74/0xd0<br /> process_pending_requests from lcd_dma_irq_handler+0x50/0x74<br /> lcd_dma_irq_handler from __handle_irq_event_percpu+0x44/0x130<br /> __handle_irq_event_percpu from handle_irq_event+0x28/0x68<br /> handle_irq_event from handle_level_irq+0x9c/0x170<br /> handle_level_irq from generic_handle_domain_irq+0x2c/0x3c<br /> generic_handle_domain_irq from omap1_handle_irq+0x40/0x8c<br /> omap1_handle_irq from generic_handle_arch_irq+0x28/0x3c<br /> generic_handle_arch_irq from call_with_stack+0x1c/0x24<br /> call_with_stack from __irq_svc+0x94/0xa8<br /> Exception stack(0xc5255da0 to 0xc5255de8)<br /> 5da0: 00000001 c22fc620 00000000 00000000 c08384a8 c106fc00 00000000 c240c248<br /> 5dc0: c113a600 c3f6ec30 00000001 00000000 c22fc620 c5255df0 c22fc620 c0279a94<br /> 5de0: 60000013 ffffffff<br /> __irq_svc from clk_prepare_lock+0x4c/0xe4<br /> clk_prepare_lock from clk_get_rate+0x10/0x74<br /> clk_get_rate from uwire_setup_transfer+0x40/0x180<br /> uwire_setup_transfer from spi_bitbang_transfer_one+0x2c/0x9c<br /> spi_bitbang_transfer_one from spi_transfer_one_message+0x2d0/0x664<br /> spi_transfer_one_message from __spi_pump_transfer_message+0x29c/0x498<br /> __spi_pump_transfer_message from __spi_sync+0x1f8/0x2e8<br /> __spi_sync from spi_sync+0x24/0x40<br /> spi_sync from ads7846_halfd_read_state+0x5c/0x1c0<br /> ads7846_halfd_read_state from ads7846_irq+0x58/0x348<br /> ads7846_irq from irq_thread_fn+0x1c/0x78<br /> irq_thread_fn from irq_thread+0x120/0x228<br /> irq_thread from kthread+0xc8/0xe8<br /> kthread from ret_from_fork+0x14/0x28<br /> <br /> As a quick fix, switch to a threaded IRQ which provides a stable system.