freebsd boot error: panic: vm_phys_enq_range: page ADDR and npages NUM are misaligned

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1a7fcf6d51eb vm_phys_enqueue_contig: handle npages==0
git tree: freebsd-src
console output: https://syzkaller.appspot.com/x/log.txt?x=110ed76ea80000
dashboard link: https://syzkaller.appspot.com/bug?extid=daa680cf9d09aaabf3cf

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+daa680...@syzkaller.appspotmail.com

panic: vm_phys_enq_range: page 0xfffffe0000000000 and npages 0 are misaligned
cpuid = 0
time = 1
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0xc6/frame 0xffffffff849799b0
kdb_backtrace() at kdb_backtrace+0xd0/frame 0xffffffff84979b10
vpanic() at vpanic+0x24b/frame 0xffffffff84979bf0
panic() at panic+0xb5/frame 0xffffffff84979cb0
vm_phys_enq_range() at vm_phys_enq_range+0x2a7/frame 0xffffffff84979d00
vm_phys_enqueue_contig() at vm_phys_enqueue_contig+0x17c/frame 0xffffffff84979d70
vm_page_startup() at vm_page_startup+0x1458/frame 0xffffffff84979e90
vm_mem_init() at vm_mem_init+0x2d/frame 0xffffffff84979eb0
mi_startup() at mi_startup+0x4b7/frame 0xffffffff84979ff0
btext() at btext+0x3d
KDB: enter: panic


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[Mark Johnston]

On Tue, Aug 01, 2023 at 10:04:13PM -0700, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 1a7fcf6d51eb vm_phys_enqueue_contig: handle npages==0
> git tree: freebsd-src
> console output: https://syzkaller.appspot.com/x/log.txt?x=110ed76ea80000
> dashboard link: https://syzkaller.appspot.com/bug?extid=daa680cf9d09aaabf3cf
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+daa680...@syzkaller.appspotmail.com
>
> panic: vm_phys_enq_range: page 0xfffffe0000000000 and npages 0 are misaligned
> cpuid = 0
> time = 1
> KDB: stack backtrace:
> db_trace_self_wrapper() at db_trace_self_wrapper+0xc6/frame 0xffffffff849799b0
> kdb_backtrace() at kdb_backtrace+0xd0/frame 0xffffffff84979b10
> vpanic() at vpanic+0x24b/frame 0xffffffff84979bf0
> panic() at panic+0xb5/frame 0xffffffff84979cb0
> vm_phys_enq_range() at vm_phys_enq_range+0x2a7/frame 0xffffffff84979d00
> vm_phys_enqueue_contig() at vm_phys_enqueue_contig+0x17c/frame 0xffffffff84979d70
> vm_page_startup() at vm_page_startup+0x1458/frame 0xffffffff84979e90
> vm_mem_init() at vm_mem_init+0x2d/frame 0xffffffff84979eb0
> mi_startup() at mi_startup+0x4b7/frame 0xffffffff84979ff0
> btext() at btext+0x3d
> KDB: enter: panic

#syz fix: Revert "vm_phys_enqueue_contig: handle npages==0"