From: Nathan Chancellor nathan@kernel.org
[ Upstream commit be185c2988b48db65348d94168c793bdbc8d23c3 ]
Commit 48667f676189 ("cxl/core: Split decoder setup into alloc + add") aimed to fix a large stack frame warning but from v5 to v6, it introduced a new instance of the warning due to allocating cxld_const_init on the stack, which was done due to the use of const on the nr_target member of the cxl_decoder struct. With ARCH=arm allmodconfig minus CONFIG_KASAN:
GCC 11.2.0:
drivers/cxl/core/bus.c: In function ‘cxl_decoder_alloc’: drivers/cxl/core/bus.c:523:1: error: the frame size of 1032 bytes is larger than 1024 bytes [-Werror=frame-larger-than=] 523 | } | ^ cc1: all warnings being treated as errors
Clang 12.0.1:
drivers/cxl/core/bus.c:486:21: error: stack frame size of 1056 bytes in function 'cxl_decoder_alloc' [-Werror,-Wframe-larger-than=] struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets) ^ 1 error generated.
Revert that part of the change, which makes the stack frame of cxl_decoder_alloc() much more reasonable.
Fixes: 48667f676189 ("cxl/core: Split decoder setup into alloc + add") Link: https://github.com/ClangBuiltLinux/linux/issues/1539 Signed-off-by: Nathan Chancellor nathan@kernel.org Link: https://lore.kernel.org/r/20211210213627.2477370-1-nathan@kernel.org Signed-off-by: Dan Williams dan.j.williams@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/cxl/core/bus.c | 6 ++---- drivers/cxl/cxl.h | 2 +- 2 files changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/cxl/core/bus.c b/drivers/cxl/core/bus.c index ebd061d039508..46ce58376580b 100644 --- a/drivers/cxl/core/bus.c +++ b/drivers/cxl/core/bus.c @@ -485,9 +485,7 @@ out_unlock:
struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets) { - struct cxl_decoder *cxld, cxld_const_init = { - .nr_targets = nr_targets, - }; + struct cxl_decoder *cxld; struct device *dev; int rc = 0;
@@ -497,13 +495,13 @@ struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets) cxld = kzalloc(struct_size(cxld, target, nr_targets), GFP_KERNEL); if (!cxld) return ERR_PTR(-ENOMEM); - memcpy(cxld, &cxld_const_init, sizeof(cxld_const_init));
rc = ida_alloc(&port->decoder_ida, GFP_KERNEL); if (rc < 0) goto err;
cxld->id = rc; + cxld->nr_targets = nr_targets; dev = &cxld->dev; device_initialize(dev); device_set_pm_not_required(dev); diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 3af704e9b448e..7c2b51746e318 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -191,7 +191,7 @@ struct cxl_decoder { int interleave_granularity; enum cxl_decoder_type target_type; unsigned long flags; - const int nr_targets; + int nr_targets; struct cxl_dport *target[]; };