Skip to content
Commit 899857dd authored by Adrian Hunter's avatar Adrian Hunter Committed by Greg Kroah-Hartman
Browse files

perf/x86/intel/pt: Fix a topa_entry base address calculation

commit ad971963 upstream.

topa_entry->base is a bit-field. Bit-fields are not promoted to a 64-bit
type, even if the underlying type is 64-bit, and so, if necessary, must
be cast to a larger type when calculations are done.

Fix a topa_entry->base address calculation by adding a cast.

Without the cast, the address was limited to 36-bits i.e. 64GiB.

The address calculation is used on systems that do not support Multiple
Entry ToPA (only Broadwell), and affects physical addresses on or above
64GiB. Instead of writing to the correct address, the address comprising
the first 36 bits would be written to.

Intel PT snapshot and sampling modes are not affected.

Fixes: 52ca9ced

 ("perf/x86/intel/pt: Add Intel PT PMU driver")
Reported-by: default avatarDave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240624201101.60186-3-adrian.hunter@intel.com
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 8f5f3db3
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment