[PATCH v1 2/3] Documentation: Update the new SIGBUS behaviour for tasks

From: Balbir Singh
Date: Tue Nov 17 2020 - 18:50:07 EST


Update the documentation to mention that a SIGBUS will be sent
to tasks that opt-into L1D flushing and execute on non-SMT cores.

Signed-off-by: Balbir Singh <sblbir@xxxxxxxxxx>
---
To be applied on top of tip commit id
767d46ab566dd489733666efe48732d523c8c332

Documentation/admin-guide/hw-vuln/l1d_flush.rst | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/Documentation/admin-guide/hw-vuln/l1d_flush.rst b/Documentation/admin-guide/hw-vuln/l1d_flush.rst
index adc4ecc72361..c6a0713c8271 100644
--- a/Documentation/admin-guide/hw-vuln/l1d_flush.rst
+++ b/Documentation/admin-guide/hw-vuln/l1d_flush.rst
@@ -63,8 +63,8 @@ This can be addressed by controlled placement of processes on physical CPU
cores or by disabling SMT. See the relevant chapter in the L1TF mitigation
document: :ref:`Documentation/admin-guide/hw-vuln/l1tf.rst <smt_control>`.

-**NOTE** : Checks have been added to ensure that the prctl API associated
+**NOTE** : Checks have been added to ensure that the L1D flush associated
with the opt-in will work only when the task affinity of the task opting
-in, is limited to cores running in non-SMT mode. The same checks are made
-when L1D is flushed. Changing the affinity after opting in, would result
-in flushes not working on cores that are in non-SMT mode.
+in, is limited to cores running in non-SMT mode. Changing the affinity after
+opting in, would result in the task getting a SIGBUS when it executes on
+the flush is needed and the task is executing on the non-SMT core.
--
2.17.1