[RFC PATCH v2 0/4] Enable strict percpu address space checks
From: Uros Bizjak
Date: Mon Aug 12 2024 - 08:00:10 EST
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 sparse doesn't know anything about __typeof_unqual__()
operator, so the usage of __typeof_unqual__() breaks sparse checking.
Cc: Dennis Zhou <dennis@xxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Nadav Amit <nadav.amit@xxxxxxxxx>
Cc: Brian Gerst <brgerst@xxxxxxxxx>
Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
Uros Bizjak (4):
percpu: Define pcpu_typeof()
percpu: Assorted fixes found by strict percpu address space checks
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 | 53 ++++++++++++++++++++++++----------
arch/x86/kernel/head64.c | 3 +-
drivers/base/devres.c | 2 +-
fs/aio.c | 2 +-
include/asm-generic/percpu.h | 41 +++++++++++++++++---------
include/linux/cleanup.h | 4 +--
include/linux/compiler_types.h | 2 +-
include/linux/part_stat.h | 2 +-
include/linux/percpu-defs.h | 39 ++++++++++++++++++++-----
include/linux/prandom.h | 1 +
init/Kconfig | 3 ++
kernel/events/hw_breakpoint.c | 4 +--
kernel/locking/percpu-rwsem.c | 2 +-
kernel/workqueue.c | 2 +-
lib/percpu_counter.c | 2 +-
net/core/dev.c | 2 +-
16 files changed, 115 insertions(+), 49 deletions(-)
--
2.46.0