On Wed, Jul 09, 2025 at 03:35:34PM +0200, Alexis Lothoré wrote:
On Wed Jul 9, 2025 at 12:39 PM CEST, Greg KH wrote:
On Wed, Jul 09, 2025 at 12:19:01PM +0200, Alexis Lothoré wrote:
Hello stable team,
could you please backport commit 440cf77625e3 ("perf: build: Setup PKG_CONFIG_LIBDIR for cross compilation") to linux-6.6.y ?
Its absence prevents some people from building the perf tool in cross-compile environment with this kernel. The patch applies cleanly on linux-6.6.y
Is this a regression from older kernels that was broken in 6.6.y, or is this a new feature? If a new feature, why not just use perf from a newer kernel version instead?
I manage to build perf with a 5.15.x kernel, while I can't in 6.6 (with the same parameters), so yes, I would call it a regression. To clarify my wording, when I say that missing this patch prevents from building perf, it actually _breaks_ perf build, when trying to build it with libtraceevent support: In file included from /home/alexis/src/buildroot/output/build/linux-6.6.94/tools/perf//util/session.h:5, from builtin-c2c.c:29: /home/alexis/src/buildroot/output/build/linux-6.6.94/tools/perf//util/trace-event.h:149:62: error: operator '&&' has no right operand 149 | #if defined(LIBTRACEEVENT_VERSION) && LIBTRACEEVENT_VERSION >= MAKE_LIBTRACEEVENT_VERSION(1, 5, 0)
Fair enough, thanks!
Note, I never can seem to build perf in the "older" LTS kernels, so I'm amazed it works at all for you :)
I'll queue this up after this round of releases goes out later this week.
greg k-h