Commit f68c7f539b ("iommu/vt-d: Enable write protect for supervisor
SVM") added pasid_enable_wpe() which hit below compile error with !X86.
../drivers/iommu/intel/pasid.c: In function 'pasid_enable_wpe':
../drivers/iommu/intel/pasid.c:554:22: error: implicit declaration of function 'read_cr0' [-Werror=implicit-function-declaration]
554 | unsigned long cr0 = read_cr0();
| ^~~~~~~~
In file included from ../include/linux/build_bug.h:5,
from ../include/linux/bits.h:22,
from ../include/linux/bitops.h:6,
from ../drivers/iommu/intel/pasid.c:12:
../drivers/iommu/intel/pasid.c:557:23: error: 'X86_CR0_WP' undeclared (first use in this function)
557 | if (unlikely(!(cr0 & X86_CR0_WP))) {
| ^~~~~~~~~~
../include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
78 | # define unlikely(x) __builtin_expect(!!(x), 0)
| ^
../drivers/iommu/intel/pasid.c:557:23: note: each undeclared identifier is reported only once for each function it appears in
557 | if (unlikely(!(cr0 & X86_CR0_WP))) {
| ^~~~~~~~~~
../include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
78 | # define unlikely(x) __builtin_expect(!!(x), 0)
|
Add the missing dependency.
Cc: Sanjay Kumar <sanjay.k.kumar@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: f68c7f539b ("iommu/vt-d: Enable write protect for supervisor SVM")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Link: https://lore.kernel.org/r/20210411062312.3057579-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
When a present pasid entry is disassembled, all kinds of pasid related
caches need to be flushed. But when a pasid entry is not being used
(PRESENT bit not set), we don't need to do this. Check the PRESENT bit
in intel_pasid_tear_down_entry() and avoid flushing caches if it's not
set.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210320025415.641201-6-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The Intel VT-d driver checks wrong register to report snoop capablility
when using first level page table for GPA to HPA translation. This might
lead the IOMMU driver to say that it supports snooping control, but in
reality, it does not. Fix this by always setting PASID-table-entry.PGSNP
whenever a pasid entry is setting up for GPA to HPA translation so that
the IOMMU driver could report snoop capability as long as it runs in the
scalable mode.
Fixes: b802d070a5 ("iommu/vt-d: Use iova over first level")
Suggested-by: Rajesh Sankaran <rajesh.sankaran@intel.com>
Suggested-by: Kevin Tian <kevin.tian@intel.com>
Suggested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210330021145.13824-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The pasid_lock is used to synchronize different threads from modifying a
same pasid directory entry at the same time. It causes below lockdep splat.
[ 83.296538] ========================================================
[ 83.296538] WARNING: possible irq lock inversion dependency detected
[ 83.296539] 5.12.0-rc3+ #25 Tainted: G W
[ 83.296539] --------------------------------------------------------
[ 83.296540] bash/780 just changed the state of lock:
[ 83.296540] ffffffff82b29c98 (device_domain_lock){..-.}-{2:2}, at:
iommu_flush_dev_iotlb.part.0+0x32/0x110
[ 83.296547] but this lock took another, SOFTIRQ-unsafe lock in the past:
[ 83.296547] (pasid_lock){+.+.}-{2:2}
[ 83.296548]
and interrupts could create inverse lock ordering between them.
[ 83.296549] other info that might help us debug this:
[ 83.296549] Chain exists of:
device_domain_lock --> &iommu->lock --> pasid_lock
[ 83.296551] Possible interrupt unsafe locking scenario:
[ 83.296551] CPU0 CPU1
[ 83.296552] ---- ----
[ 83.296552] lock(pasid_lock);
[ 83.296553] local_irq_disable();
[ 83.296553] lock(device_domain_lock);
[ 83.296554] lock(&iommu->lock);
[ 83.296554] <Interrupt>
[ 83.296554] lock(device_domain_lock);
[ 83.296555]
*** DEADLOCK ***
Fix it by replacing the pasid_lock with an atomic exchange operation.
Reported-and-tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210320020916.640115-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
DevTLB flush can be used for both DMA request with and without PASIDs.
The former uses PASID#0 (RID2PASID), latter uses non-zero PASID for SVA
usage.
This patch adds a check for PASID value such that devTLB flush with
PASID is used for SVA case. This is more efficient in that multiple
PASIDs can be used by a single device, when tearing down a PASID entry
we shall flush only the devTLB specific to a PASID.
Fixes: 6f7db75e1c ("iommu/vt-d: Add second level page table")
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20200724014925.15523-4-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
