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-rw-r--r--Documentation/PCI/MSI-HOWTO.txt15
1 files changed, 3 insertions, 12 deletions
diff --git a/Documentation/PCI/MSI-HOWTO.txt b/Documentation/PCI/MSI-HOWTO.txt
index 0d920d54536d..63def8ef546d 100644
--- a/Documentation/PCI/MSI-HOWTO.txt
+++ b/Documentation/PCI/MSI-HOWTO.txt
@@ -501,18 +501,9 @@ necessary to disable interrupts (Linux guarantees the same interrupt will
not be re-entered). If a device uses multiple interrupts, the driver
must disable interrupts while the lock is held. If the device sends
a different interrupt, the driver will deadlock trying to recursively
-acquire the spinlock.
-
-There are two solutions. The first is to take the lock with
-spin_lock_irqsave() or spin_lock_irq() (see
-Documentation/DocBook/kernel-locking). The second is to specify
-IRQF_DISABLED to request_irq() so that the kernel runs the entire
-interrupt routine with interrupts disabled.
-
-If your MSI interrupt routine does not hold the lock for the whole time
-it is running, the first solution may be best. The second solution is
-normally preferred as it avoids making two transitions from interrupt
-disabled to enabled and back again.
+acquire the spinlock. Such deadlocks can be avoided by using
+spin_lock_irqsave() or spin_lock_irq() which disable local interrupts
+and acquire the lock (see Documentation/DocBook/kernel-locking).
4.6 How to tell whether MSI/MSI-X is enabled on a device