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| author | Lu Baolu <baolu.lu@linux.intel.com> | 2019-06-12 08:28:49 +0800 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2019-06-12 10:36:59 +0200 |
| commit | d5692d4af08cde48ee98968aeb62077e2f6c50d5 (patch) | |
| tree | 9a1d303e1d7314ce4fac7d1a0b359ffbfad1c926 /drivers/iommu/intel-iommu.c | |
| parent | 5679582c2fad11733ba65c12d127f9d703390e55 (diff) | |
| download | linux-d5692d4af08cde48ee98968aeb62077e2f6c50d5.tar.gz linux-d5692d4af08cde48ee98968aeb62077e2f6c50d5.tar.bz2 linux-d5692d4af08cde48ee98968aeb62077e2f6c50d5.zip | |
iommu/vt-d: Fix suspicious RCU usage in probe_acpi_namespace_devices()
The drhd and device scope list should be iterated with the
iommu global lock held. Otherwise, a suspicious RCU usage
message will be displayed.
[ 3.695886] =============================
[ 3.695917] WARNING: suspicious RCU usage
[ 3.695950] 5.2.0-rc2+ #2467 Not tainted
[ 3.695981] -----------------------------
[ 3.696014] drivers/iommu/intel-iommu.c:4569 suspicious rcu_dereference_check() usage!
[ 3.696069]
other info that might help us debug this:
[ 3.696126]
rcu_scheduler_active = 2, debug_locks = 1
[ 3.696173] no locks held by swapper/0/1.
[ 3.696204]
stack backtrace:
[ 3.696241] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc2+ #2467
[ 3.696370] Call Trace:
[ 3.696404] dump_stack+0x85/0xcb
[ 3.696441] intel_iommu_init+0x128c/0x13ce
[ 3.696478] ? kmem_cache_free+0x16b/0x2c0
[ 3.696516] ? __fput+0x14b/0x270
[ 3.696550] ? __call_rcu+0xb7/0x300
[ 3.696583] ? get_max_files+0x10/0x10
[ 3.696631] ? set_debug_rodata+0x11/0x11
[ 3.696668] ? e820__memblock_setup+0x60/0x60
[ 3.696704] ? pci_iommu_init+0x16/0x3f
[ 3.696737] ? set_debug_rodata+0x11/0x11
[ 3.696770] pci_iommu_init+0x16/0x3f
[ 3.696805] do_one_initcall+0x5d/0x2e4
[ 3.696844] ? set_debug_rodata+0x11/0x11
[ 3.696880] ? rcu_read_lock_sched_held+0x6b/0x80
[ 3.696924] kernel_init_freeable+0x1f0/0x27c
[ 3.696961] ? rest_init+0x260/0x260
[ 3.696997] kernel_init+0xa/0x110
[ 3.697028] ret_from_fork+0x3a/0x50
Fixes: fa212a97f3a36 ("iommu/vt-d: Probe DMA-capable ACPI name space devices")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/intel-iommu.c')
| -rw-r--r-- | drivers/iommu/intel-iommu.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index c31fbe5790c7..9761ac366e3f 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -4821,8 +4821,10 @@ int __init intel_iommu_init(void) cpuhp_setup_state(CPUHP_IOMMU_INTEL_DEAD, "iommu/intel:dead", NULL, intel_iommu_cpu_dead); + down_read(&dmar_global_lock); if (probe_acpi_namespace_devices()) pr_warn("ACPI name space devices didn't probe correctly\n"); + up_read(&dmar_global_lock); /* Finally, we enable the DMA remapping hardware. */ for_each_iommu(iommu, drhd) { |