I am sorry for the late reply. I fully agree with your patch. It was my mistake. I should have to allocate the buffer with gfp flags. Thank you for the corrections.
On 2026년 8월 18일 오후 6시 6분 37초 GMT+09:00, Breno Leitao <[email protected]> 작성함: >On Mon, Aug 10, 2026 at 09:40:00AM -0700, Breno Leitao wrote: >> put_chars() runs from the hvc console write path with preemption >> disabled, so it asks alloc_buf() for GFP_ATOMIC. Only the data buffer >> gets it: the struct port_buffer itself keeps the GFP_KERNEL default, so >> the allocation can enter direct reclaim and sleep. A write to /dev/kmsg >> on a CONFIG_DEBUG_ATOMIC_SLEEP kernel splats: >> >> BUG: sleeping function called from invalid context at >> ./include/linux/sched/mm.h:320 >> in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: >> virtme-ng-init >> preempt_count: 1, expected: 0 >> Preemption disabled at: >> [<ffffffff813fd90d>] vprintk_emit+0x17d/0x510 >> Call Trace: >> <TASK> >> dump_stack_lvl+0x69/0xa0 >> __might_resched+0x37a/0x4d0 >> __kmalloc_cache_noprof+0x94/0x5f0 >> put_chars+0x209/0x3e0 >> hvc_console_print+0x234/0x640 >> console_flush_all+0x4fc/0x950 >> console_unlock+0xbf/0x1b0 >> vprintk_emit+0x312/0x510 >> devkmsg_emit+0xba/0x110 >> devkmsg_write+0x21b/0x2e0 >> vfs_write+0x4dc/0x9d0 >> ksys_write+0x108/0x1e0 >> do_syscall_64+0xfa/0x460 >> </TASK> >> >> Pass gfp on to that allocation too. >> >> Fixes: fc220d6be3c7 ("virtio_console: refactor __send_to_port() buffer >> ownership") >> Signed-off-by: Breno Leitao <[email protected]> > >Ping? >
