On Tue, 20 Jul 2021 23:48:47 +0200 Pavel Machek pavel@denx.de wrote:
Hi!
[ Upstream commit a948b1142cae66785521a389cab2cce74069b547 ]
Since commit 9a6944fee68e ("tracing: Add a verifier to check string pointers for trace events"), which was merged in v5.13-rc1, TP_printk() no longer tacitly supports the "%.*s" format specifier.
These are low value tracepoints, so just remove them.
So I understand we want this for mainline, but AFAICT 5.10 does not have 9a6944fee68e ("tracing: Add a verifier to check string pointers for trace events") commit, so this does not fix any bug and removal of tracepoints can be surprising.
Thanks for pointing this out. I get so many stable patches, I don't have time to look at all of them.
Greg, I don't think this should be backported. The verifier code had a bug in it that broke the '%.*s' formats. This patch removed the good code because of the broken code.
See eb01f5353bdaa ("tracing: Handle %.*s in trace_check_vprintf()")
-- Steve