Re: [syzbot] [iommu?] WARNING in intel_iommu_map_pages

[Baolu Lu]

On 9/23/25 00:55, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:    3b08f56fbbb9 Merge tag 'x86-urgent-2025-09-20' ofgit://gi..
> git tree:       upstream
> console output:https://syzkaller.appspot.com/x/log.txt?x=142d3c7c580000
> kernel config:https://syzkaller.appspot.com/x/.config?x=8f01d8629880e620
> dashboard link:https://syzkaller.appspot.com/bug?extid=6e970ad52c1b9e57e6b1
> compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:https://syzkaller.appspot.com/x/repro.syz?x=1740fe42580000
> C reproducer:https://syzkaller.appspot.com/x/repro.c?x=1037a712580000
>
> Downloadable assets:
> disk image (non-bootable):https://storage.googleapis.com/syzbot-assets/d900f083ada3/ 
> non_bootable_disk-3b08f56f.raw.xz
> vmlinux:https://storage.googleapis.com/syzbot-assets/6f981dad47cf/ 
> vmlinux-3b08f56f.xz
> kernel image:https://storage.googleapis.com/syzbot-assets/031397abeebd/ 
> bzImage-3b08f56f.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by:syzbot+6e970ad52c1b9e57e6b1@xxxxxxxxxxxxxxxxxxxxxxxxx
>
> DMAR: ERROR: DMA PTE for vPFN 0xbe300 already set (to 55400003 not 51800003)

The driver is complaining that the PTE entry for IOVA 0xbe300 was mapped
to 0x55400000, but not unmapped before remapping it to 0x51800003.

Thanks,
baolu