Re: WARN_ON_ONCE(1) in iomap_dio_actor()

2020-08-17 Thread Christoph Hellwig
On Thu, Aug 13, 2020 at 03:52:13AM -0400, Qian Cai wrote: > > No sane application would ever do this, it's behaviour as expected, > > so I don't think there's anything to care about here. > > It looks me the kernel warning is trivial to trigger by an non-root user. > Shouldn???t we worry a bit

Re: WARN_ON_ONCE(1) in iomap_dio_actor()

2020-08-13 Thread Qian Cai
> On Aug 13, 2020, at 1:44 AM, Dave Chinner wrote: > > Ok: > > file.fd_write = safe_open("./testfile", O_RDWR|O_CREAT); > > file.fd_read = safe_open("./testfile", O_RDWR|O_CREAT|O_DIRECT); > > file.ptr = safe_mmap(NULL, fsize, PROT_READ|PROT_WRITE, MAP_SHARED, >

Re: WARN_ON_ONCE(1) in iomap_dio_actor()

2020-08-12 Thread Dave Chinner
On Mon, Aug 10, 2020 at 10:03:03PM -0400, Qian Cai wrote: > On Sun, Jul 26, 2020 at 04:24:12PM +0100, Christoph Hellwig wrote: > > On Fri, Jul 24, 2020 at 02:24:32PM -0400, Qian Cai wrote: > > > On Fri, Jun 19, 2020 at 05:17:47PM -0700, Matthew Wilcox wrote: > > > > On Fri, Jun 19, 2020 at

Re: WARN_ON_ONCE(1) in iomap_dio_actor()

2020-08-10 Thread Qian Cai
On Sun, Jul 26, 2020 at 04:24:12PM +0100, Christoph Hellwig wrote: > On Fri, Jul 24, 2020 at 02:24:32PM -0400, Qian Cai wrote: > > On Fri, Jun 19, 2020 at 05:17:47PM -0700, Matthew Wilcox wrote: > > > On Fri, Jun 19, 2020 at 05:17:50PM -0400, Qian Cai wrote: > > > > Running a syscall fuzzer by a

Re: WARN_ON_ONCE(1) in iomap_dio_actor()

2020-07-26 Thread Qian Cai
On Sun, Jul 26, 2020 at 04:24:12PM +0100, Christoph Hellwig wrote: > On Fri, Jul 24, 2020 at 02:24:32PM -0400, Qian Cai wrote: > > On Fri, Jun 19, 2020 at 05:17:47PM -0700, Matthew Wilcox wrote: > > > On Fri, Jun 19, 2020 at 05:17:50PM -0400, Qian Cai wrote: > > > > Running a syscall fuzzer by a

Re: WARN_ON_ONCE(1) in iomap_dio_actor()

2020-07-26 Thread Christoph Hellwig
On Fri, Jul 24, 2020 at 02:24:32PM -0400, Qian Cai wrote: > On Fri, Jun 19, 2020 at 05:17:47PM -0700, Matthew Wilcox wrote: > > On Fri, Jun 19, 2020 at 05:17:50PM -0400, Qian Cai wrote: > > > Running a syscall fuzzer by a normal user could trigger this, > > > > > > [55649.32][T515839]

Re: WARN_ON_ONCE(1) in iomap_dio_actor()

2020-07-24 Thread Qian Cai
On Fri, Jun 19, 2020 at 05:17:47PM -0700, Matthew Wilcox wrote: > On Fri, Jun 19, 2020 at 05:17:50PM -0400, Qian Cai wrote: > > Running a syscall fuzzer by a normal user could trigger this, > > > > [55649.32][T515839] WARNING: CPU: 6 PID: 515839 at > > fs/iomap/direct-io.c:391

Re: WARN_ON_ONCE(1) in iomap_dio_actor()

2020-06-20 Thread Qian Cai
On Fri, Jun 19, 2020 at 05:17:47PM -0700, Matthew Wilcox wrote: > On Fri, Jun 19, 2020 at 05:17:50PM -0400, Qian Cai wrote: > > Running a syscall fuzzer by a normal user could trigger this, > > > > [55649.32][T515839] WARNING: CPU: 6 PID: 515839 at > > fs/iomap/direct-io.c:391

Re: WARN_ON_ONCE(1) in iomap_dio_actor()

2020-06-19 Thread Matthew Wilcox
On Fri, Jun 19, 2020 at 05:17:50PM -0400, Qian Cai wrote: > Running a syscall fuzzer by a normal user could trigger this, > > [55649.32][T515839] WARNING: CPU: 6 PID: 515839 at > fs/iomap/direct-io.c:391 iomap_dio_actor+0x29c/0x420 ... > 371 static loff_t > 372 iomap_dio_actor(struct inode

WARN_ON_ONCE(1) in iomap_dio_actor()

2020-06-19 Thread Qian Cai
Running a syscall fuzzer by a normal user could trigger this, [55649.32][T515839] WARNING: CPU: 6 PID: 515839 at fs/iomap/direct-io.c:391 iomap_dio_actor+0x29c/0x420 [55649.339490][T515839] Modules linked in: vfio_pci vfio_virqfd vfio_iommu_type1 vfio processor efivarfs ip_tables x_tables