Kernel warning in reserve_pfn_range with 2.6.29-rc kernels

[Robert Hancock]

When starting a VirtualBox virtual machine with Linux 2.6.29-rc4 as the host kernel, I'm getting this kernel warning showing up:

WARNING: at arch/x86/mm/pat.c:637 reserve_pfn_range+0x5b/0x26d()
Hardware name: System name
Modules linked in: vboxnetflt vboxdrv ipv6 it87 hwmon_vid adm1021 cpufreq_ondemand powernow_k8 freq_table fuse dm_multipath uinput snd_ice1724 snd_rawmidi snd_ice17xx_ak4xxx snd_ac97_codec ac97_bus snd_ak4xxx_adda snd_ak4114 snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss snd_pcm nvidia(P) snd_timer snd_page_alloc gspca_spca561 snd_pt2258 snd_i2c gspca_main snd usb_storage videodev firewire_ohci k8temp floppy firewire_core hwmon crc_itu_t soundcore pcspkr sata_sil serio_raw forcedeth pata_amd v4l1_compat v4l2_compat_ioctl32 i2c_nforce2 i2c_core joydev ata_generic pata_acpi sata_nv ext4 jbd2 crc16 [last unloaded: scsi_wait_scan]
Pid: 4415, comm: VirtualBox Tainted: P           2.6.29-rc4 #5
Call Trace:
 [<ffffffff810490e1>] warn_slowpath+0xb1/0xed
 [<ffffffff8115216a>] ? selinux_inode_alloc_security+0x5d/0x8f
 [<ffffffff8115ecdc>] ? security_transition_sid+0x14/0x16
 [<ffffffff8115199b>] ? inode_doinit_with_dentry+0x436/0x44c
 [<ffffffff810de91e>] ? new_inode+0x65/0x73
 [<ffffffff8135d00d>] ? _spin_lock+0x9/0xc
 [<ffffffff810e06b5>] ? mnt_want_write+0x7e/0x95
 [<ffffffff811519c8>] ? selinux_d_instantiate+0x17/0x19
 [<ffffffff81033b13>] reserve_pfn_range+0x5b/0x26d
 [<ffffffff81033d70>] track_pfn_vma_new+0x4b/0xb7
 [<ffffffff810af17a>] remap_pfn_range+0xaf/0x38c
 [<ffffffff810b406f>] ? do_mmap_pgoff+0x2f6/0x359
 [<ffffffffa0a3f39c>] rtR0MemObjNativeMapUser+0x157/0x272 [vboxdrv]
 [<ffffffffa0a3d01e>] RTR0MemObjMapUser+0x130/0x1dc [vboxdrv]
 [<ffffffffa0a391be>] SUPR0GipMap+0x125/0x216 [vboxdrv]
 [<ffffffffa0a3c2bf>] supdrvIOCtl+0x1028/0x1538 [vboxdrv]
 [<ffffffffa0a3e83e>] ? rtMemAlloc+0x92/0xc7 [vboxdrv]
 [<ffffffffa0a3e7a5>] ? rtMemFree+0x65/0x6c [vboxdrv]
 [<ffffffffa0a38260>] VBoxDrvLinuxIOCtl+0x120/0x19f [vboxdrv]
 [<ffffffff810d832c>] vfs_ioctl+0x2a/0x78
 [<ffffffff810d87f8>] do_vfs_ioctl+0x462/0x4a2
 [<ffffffff810cc0cc>] ? fsnotify_access+0x62/0x6a
 [<ffffffff810d888d>] sys_ioctl+0x55/0x77
 [<ffffffff8101133a>] system_call_fastpath+0x16/0x1b
---[ end trace ae7d0c69b5264633 ]---

[Robert Hancock]

This is this warning:

	if (is_ram != 0) {
		/*
		 * For mapping RAM pages, drivers need to call
		 * set_memory_[uc|wc|wb] directly, for reserve and free, before
		 * setting up the PTE.
		 */
		WARN_ON_ONCE(1);
		return 0;
	}

[Robert Hancock]

Still a problem in VirtualBox 2.1.4.

[Robert Hancock]

With 2.6.29-rc6 I get the problem described here:

​http://www.virtualbox.org/ticket/3403

The solution of uncommenting

# VBOX_USE_INSERT_PAGE = 1

in /usr/src/vboxdrv*/Makefile appears to resolve both issues.

[Frank Mehnert]

Let's continue on #3403 then.