lib/ukdebug: Mark tracepoint sections as unallocated notes

At runtime we don't care about the content of them, and we only need
them on host side to decode the trace buffer.
This also prevents the linker from adding a segment for these sections.
Because the resulting segment sometimes only contained these two
sections, the final `strip` step would end up with an empty segment.
And in the case of the linuxu platform the resulting image was not
working anymore.

Signed-off-by: Marco Schlumpp <marco@unikraft.io>
Reviewed-by: Sergiu Moga <sergiu.moga@protonmail.com>
Reviewed-by: Razvan Deaconescu <razvand@unikraft.io>
Approved-by: Razvan Deaconescu <razvand@unikraft.io>
Tested-by: Unikraft CI <monkey@unikraft.io>
GitHub-Closes: #833

diff --git a/lib/ukdebug/include/uk/trace.h b/lib/ukdebug/include/uk/trace.h
index 89148c323652bbc31d926c7a37bccf89c2290d6f..9c4819461582f38049e9137128eeb6739d7d7aa6 100644 (file)
--- a/lib/ukdebug/include/uk/trace.h
+++ b/lib/ukdebug/include/uk/trace.h
@@ -173,7 +173,8 @@ static inline void __uk_trace_save_arg(char **pbuff,
 #define __UK_TRACE_REG(NR, regname, trace_name, fmt, ...)      \
        UK_CTASSERT(sizeof(#trace_name) < 255);                 \
        UK_CTASSERT(sizeof(fmt) < 255);                         \
-       __attribute((__section__(".uk_tracepoints_list")))      \
+       __attribute((__section__(                               \
+               ".uk_tracepoints_list,\"\",@note#")))           \
        static struct {                                         \
                uint32_t magic;                                 \
                uint32_t size;                                  \

diff --git a/lib/ukdebug/trace.c b/lib/ukdebug/trace.c
index 2572560c163017f43ca0bac2748ffbf9b8f0fecf..7721ea717bf83bc78e565f7a0e84b57ba20bdc4b 100644 (file)
--- a/lib/ukdebug/trace.c
+++ b/lib/ukdebug/trace.c
@@ -54,7 +54,8 @@ char *uk_trace_buffer_writep = uk_trace_buffer;
  *     $ readelf -p .uk_trace_keyvals <your_image.gdb>
  */
 #define TRACE_DEFINE_KEY(key, val)                     \
-       __attribute((__section__(".uk_trace_keyvals"))) \
+       __attribute((__section__(                       \
+               ".uk_trace_keyvals,\"\",@note#")))      \
        static const char key[] __used =                \
                #key " = " #val