This patchset enables strict percpu address space checks via x86 named
address space qualifiers. Percpu variables are declared in
__seg_gs/__seg_fs named AS and kept named AS qualified until they
are dereferenced via percpu accessor. This approach enables various
compiler checks for cross-namespace variable assignments.
Please note that current version of sparse doesn't know anything about
__typeof_unqual__() operator. Avoid the usage of __typeof_unqual__()
when sparse checking is active to prevent sparse errors with unknowing
keyword.
v2: - Add comment to remove test for __CHECKER__ once sparse learns
about __typeof_unqual__.
- Add Acked-by: tags.
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Dennis Zhou <dennis@xxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Nadav Amit <nadav.amit@xxxxxxxxx>
Cc: Brian Gerst <brgerst@xxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Uros Bizjak (6):
x86/kgdb: Use IS_ERR_PCPU() macro
compiler.h: Introduce TYPEOF_UNQUAL() macro
percpu: Use TYPEOF_UNQUAL() in variable declarations
percpu: Use TYPEOF_UNQUAL() in *_cpu_ptr() accessors
percpu: Repurpose __percpu tag as a named address space qualifier
percpu/x86: Enable strict percpu checks via named AS qualifiers
arch/x86/include/asm/percpu.h | 38 ++++++++++++++++++++++---------
arch/x86/kernel/kgdb.c | 2 +-
fs/bcachefs/util.h | 2 +-
include/asm-generic/percpu.h | 41 +++++++++++++++++++++++-----------
include/linux/compiler.h | 13 +++++++++++
include/linux/compiler_types.h | 2 +-
include/linux/part_stat.h | 2 +-
include/linux/percpu-defs.h | 6 ++---
include/net/snmp.h | 5 ++---
init/Kconfig | 3 +++
kernel/locking/percpu-rwsem.c | 2 +-
net/mpls/internal.h | 4 ++--
12 files changed, 84 insertions(+), 36 deletions(-)
--
2.42.0
