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// SPDX-License-Identifier: GPL-2.0
/*
* Static locals of three kinds, in one patched function.
*
* Most static locals must be correlated, so the patched code keeps using the
* running kernel's copy. Two kinds must not:
*
* - anything in .data..once, the flag behind WARN_ONCE and friends. Sharing
* it would mean a patch inherits "already warned" from before the patch.
* - the well-known names the kernel generates for such things (__warned,
* __key, __func__, ...), which are per-instance by nature. gcc names them
* <var>.<id> and Clang <func>.<var>, so both spellings have to be caught.
*/
static const char __modinfo[]
__attribute__((section(".modinfo"), used, aligned(1))) = "\0name=vmlinux";
int target(int x)
{
/*
* A .data..once variable whose name is *not* on the list below, so
* only the section can disqualify it. Naming it __warned would let
* the name rule catch it and the section rule go untested.
*/
static int once_flag __attribute__((section(".data..once")));
/* a never-correlate name, in an ordinary section */
static int __key;
/* and one that must be correlated */
static int ordinary;
if (!once_flag)
once_flag = 1;
__key += x;
ordinary += x;
#ifdef PATCHED
return __key + ordinary + once_flag + 2;
#else
return __key + ordinary + once_flag + 1;
#endif
}
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