[ Upstream commit 27646b2e02b096a6936b3e3b6ba334ae20763eab ]
It can be easy to miss that the notifier mechanism invokes the callbacks
in an atomic context, so add some comments to that effect on the two
handlers we register here.
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230829063457.54157-4-bgray@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3d2ffcdd2a982e8bbe65fa0f94fb21bf304c281e ]
POWER10 DD1 has an issue where it generates watchpoint exceptions when
it shouldn't. The conditions where this occur are:
- octword op
- ending address of DAWR range is less than starting address of op
- those addresses need to be in the same or in two consecutive 512B
blocks
- 'op address + 64B' generates an address that has a carry into bit
52 (crosses 2K boundary)
Handle such spurious exception by considering them as extraneous and
emulating/single-steeping instruction without generating an event.
[ravi: Fixed build warning reported by lkp@intel.com]
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201106045650.278987-1-ravi.bangoria@linux.ibm.com
Stable-dep-of: 27646b2e02b0 ("powerpc/watchpoints: Annotate atomic context in more places")
Signed-off-by: Sasha Levin <sashal@kernel.org>
