| Message ID | 1481007384-27529-1-git-send-email-wangkefeng.wang@huawei.com |
|---|---|
| State | Accepted |
| Commit | 166ad0e1e2132ff0cda08b94af8301655fcabbcd |
| Headers | show |
On Tue, Dec 06, 2016 at 02:56:24PM +0800, Kefeng Wang wrote: > It is needed by struct task_struct, fixes the following build problem > with old gcc: > > ../kernel/kcov.c: In function ‘__sanitizer_cov_trace_pc’: > ../kernel/kcov.c:66: error: dereferencing pointer to incomplete type > ...... > ../kernel/kcov.c:239: error: dereferencing pointer to incomplete type > It's somewhat confusing to strip the useful part of the error message (which mentions task struct). How about: In __sanitizer_cov_trace_pc we use task_struct and fields within it, but as we haven't included <linux/sched.h>, it is not guaranteed to be defined. While we usually happen to acquire the definition through a transitive include, this is fragile (and hasn't been true in the past, causing issues with backports). Include <linux/sched.h> to avoid any fragility. Either way this looks like a sensible fix/cleanup, so FWIW: Acked-by: Mark Rutland <mark.rutland@arm.com> It looks like we're missing some other headers (e.g. <linux/export.h> for EXPORT_SYMBOL(), <linux/preempt.h> for preempt_count() and friends). It may be worth fixing all of those at once. Thanks, Mark. > Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> > --- > > note: > - Build error occurred when I backported kcov to an old kernel version > with an old gcc > > kernel/kcov.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/kernel/kcov.c b/kernel/kcov.c > index 30e6d05..3cbb0c8 100644 > --- a/kernel/kcov.c > +++ b/kernel/kcov.c > @@ -7,6 +7,7 @@ > #include <linux/fs.h> > #include <linux/mm.h> > #include <linux/printk.h> > +#include <linux/sched.h> > #include <linux/slab.h> > #include <linux/spinlock.h> > #include <linux/vmalloc.h> > -- > 1.7.12.4 >
diff --git a/kernel/kcov.c b/kernel/kcov.c index 30e6d05..3cbb0c8 100644 --- a/kernel/kcov.c +++ b/kernel/kcov.c @@ -7,6 +7,7 @@ #include <linux/fs.h> #include <linux/mm.h> #include <linux/printk.h> +#include <linux/sched.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/vmalloc.h>
It is needed by struct task_struct, fixes the following build problem with old gcc: ../kernel/kcov.c: In function ‘__sanitizer_cov_trace_pc’: ../kernel/kcov.c:66: error: dereferencing pointer to incomplete type ...... ../kernel/kcov.c:239: error: dereferencing pointer to incomplete type Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> --- note: - Build error occurred when I backported kcov to an old kernel version with an old gcc kernel/kcov.c | 1 + 1 file changed, 1 insertion(+) -- 1.7.12.4