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2d33b7d631
The dev_iommu_priv_set() must be called after probe_device(). This fixes
a NULL pointer deference bug when booting a system with kernel cmdline
"intel_iommu=on,igfx_off", where the dev_iommu_priv_set() is abused.
The following stacktrace was produced:
Command line: BOOT_IMAGE=/isolinux/bzImage console=tty1 intel_iommu=on,igfx_off
...
DMAR: Host address width 39
DMAR: DRHD base: 0x000000fed90000 flags: 0x0
DMAR: dmar0: reg_base_addr fed90000 ver 1:0 cap 1c0000c40660462 ecap 19e2ff0505e
DMAR: DRHD base: 0x000000fed91000 flags: 0x1
DMAR: dmar1: reg_base_addr fed91000 ver 1:0 cap d2008c40660462 ecap f050da
DMAR: RMRR base: 0x0000009aa9f000 end: 0x0000009aabefff
DMAR: RMRR base: 0x0000009d000000 end: 0x0000009f7fffff
DMAR: No ATSR found
BUG: kernel NULL pointer dereference, address: 0000000000000038
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] SMP PTI
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.9.0-devel+ #2
Hardware name: LENOVO 20HGS0TW00/20HGS0TW00, BIOS N1WET46S (1.25s ) 03/30/2018
RIP: 0010:intel_iommu_init+0xed0/0x1136
Code: fe e9 61 02 00 00 bb f4 ff ff ff e9 57 02 00 00 48 63 d1 48 c1 e2 04 48
03 50 20 48 8b 12 48 85 d2 74 0b 48 8b 92 d0 02 00 00 48 89 7a 38 ff c1
e9 15 f5 ff ff 48 c7 c7 60 99 ac a7 49 c7 c7 a0
RSP: 0000:ffff96d180073dd0 EFLAGS: 00010282
RAX: ffff8c91037a7d20 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffffffffff
RBP: ffff96d180073e90 R08: 0000000000000001 R09: ffff8c91039fe3c0
R10: 0000000000000226 R11: 0000000000000226 R12: 000000000000000b
R13: ffff8c910367c650 R14: ffffffffa8426d60 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8c9107480000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000038 CR3: 00000004b100a001 CR4: 00000000003706e0
Call Trace:
? _raw_spin_unlock_irqrestore+0x1f/0x30
? call_rcu+0x10e/0x320
? trace_hardirqs_on+0x2c/0xd0
? rdinit_setup+0x2c/0x2c
? e820__memblock_setup+0x8b/0x8b
pci_iommu_init+0x16/0x3f
do_one_initcall+0x46/0x1e4
kernel_init_freeable+0x169/0x1b2
? rest_init+0x9f/0x9f
kernel_init+0xa/0x101
ret_from_fork+0x22/0x30
Modules linked in:
CR2: 0000000000000038
---[ end trace 3653722a6f936f18 ]---
Fixes: 01b9d4e211 ("iommu/vt-d: Use dev_iommu_priv_get/set()")
Reported-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Reported-by: Wendy Wang <wendy.wang@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Link: https://lore.kernel.org/linux-iommu/96717683-70be-7388-3d2f-61131070a96a@secunet.com/
Link: https://lore.kernel.org/r/20200903065132.16879-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.