panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x6e242f]

goroutine 646 [running]:
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*FSContext).RootDirectory(0x0, 0x0)
	pkg/sentry/kernel/fs_context.go:136 +0x2f
gvisor.googlesource.com/gvisor/pkg/sentry/fs/proc.forEachMountSource(0xc4205ae400, 0xc4206cf4d0)
	pkg/sentry/fs/proc/mounts.go:33 +0x4a
gvisor.googlesource.com/gvisor/pkg/sentry/fs/proc.(*mountInfoFile).ReadSeqFileData(0xc42061c098, 0xc72c00, 0xc4202c0d00, 0x0, 0x0, 0xc4206cf548, 0x5dc15e, 0xc4200f6550, 0x153c1ca083b656fc)
	pkg/sentry/fs/proc/mounts.go:77 +0x75
gvisor.googlesource.com/gvisor/pkg/sentry/fs/proc/seqfile.(*SeqFile).updateSourceLocked(0xc4207e2c80, 0xc72c00, 0xc4202c0d00, 0x0)
	pkg/sentry/fs/proc/seqfile/seqfile.go:225 +0x97
gvisor.googlesource.com/gvisor/pkg/sentry/fs/proc/seqfile.(*SeqFile).DeprecatedPreadv(0xc4207e2c80, 0xc72c00, 0xc4202c0d00, 0xc71940, 0xc4208fac80, 0xc42071c000, 0x205, 0x0, 0x1000, 0x100, ...)
	pkg/sentry/fs/proc/seqfile/seqfile.go:158 +0x7c3
gvisor.googlesource.com/gvisor/pkg/sentry/fs/fsutil.(*Handle).Read(0xc42019a860, 0xc72c00, 0xc4202c0d00, 0xc42021e480, 0xc71940, 0xc4208fac80, 0xc42071c000, 0x205, 0x0, 0x1000, ...)
	pkg/sentry/fs/fsutil/handle.go:90 +0x8e
gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*File).Preadv(0xc42021e480, 0xc72c00, 0xc4202c0d00, 0xc71940, 0xc4208fac80, 0xc42071c000, 0x205, 0x0, 0x1000, 0x100, ...)
	pkg/sentry/fs/file.go:248 +0x117
gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.preadv(0xc4202c0d00, 0xc42021e480, 0xc71940, 0xc4208fac80, 0xc42071c000, 0x205, 0x0, 0x1000, 0x100, 0x0, ...)
	pkg/sentry/syscalls/linux/sys_read.go:234 +0x9e
gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.Preadv(0xc4202c0d00, 0x3, 0x200023c0, 0x1000000000000205, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
	pkg/sentry/syscalls/linux/sys_read.go:185 +0x27b
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc4202c0d00, 0x127, 0x3, 0x200023c0, 0x1000000000000205, 0x0, 0x0, 0x0, 0xc4206cfca8, 0xbb3400, ...)
	pkg/sentry/kernel/task_syscall.go:162 +0x307
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc4202c0d00, 0x127, 0x3, 0x200023c0, 0x1000000000000205, 0x0, 0x0, 0x0, 0x0, 0x0)
	pkg/sentry/kernel/task_syscall.go:278 +0x62
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc4202c0d00, 0x127, 0x3, 0x200023c0, 0x1000000000000205, 0x0, 0x0, 0x0, 0xc4204de800, 0xc4206cfe00)
	pkg/sentry/kernel/task_syscall.go:241 +0x91
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc4202c0d00, 0x2, 0xc4206e2000)
	pkg/sentry/kernel/task_syscall.go:216 +0x10c
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute(0x0, 0xc4202c0d00, 0xc65e20, 0x0)
	pkg/sentry/kernel/task_run.go:217 +0xed8
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run(0xc4202c0d00, 0x26)
	pkg/sentry/kernel/task_run.go:95 +0x174
created by gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:251 +0x100