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charset="utf-8" In COVERAGE=3Dy but DEBUG=3Dn builds (observed by randconfig testing) gcc12 takes issue with the subtraction of 1 from __stop___pre_ex_table[], considering this an out of bounds access. Not being able to know that the symbol actually marks the end of an array, the compiler is kind of right with this diagnosis. Move the subtraction into the function. Reported-by: Anthony PERARD Signed-off-by: Jan Beulich --- To keep things simple, I'm merely calculating "last" as a local variable now, rather than replacing its uses by suitable ones of "end". In the longer run it may become necessary to actually go this 2nd step, as in principle the compiler could inline the function and then still spot the same issue. However, while the subtraction of 1 can likely be avoided by suitable other adjustments, "last - first" cannot easily be. Yet that's also an offense, in that it's calculating the difference between pointers into distinct objects. --- a/xen/arch/x86/extable.c +++ b/xen/arch/x86/extable.c @@ -64,9 +64,10 @@ void __init sort_exception_tables(void) =20 static unsigned long search_one_extable(const struct exception_table_entry *first, - const struct exception_table_entry *last, + const struct exception_table_entry *end, unsigned long value) { + const struct exception_table_entry *last =3D end - 1; const struct exception_table_entry *mid; long diff; =20 @@ -91,7 +92,7 @@ search_exception_table(const struct cpu_ unsigned long stub =3D this_cpu(stubs.addr); =20 if ( region && region->ex ) - return search_one_extable(region->ex, region->ex_end - 1, regs->ri= p); + return search_one_extable(region->ex, region->ex_end, regs->rip); =20 if ( regs->rip >=3D stub + STUB_BUF_SIZE / 2 && regs->rip < stub + STUB_BUF_SIZE && @@ -102,7 +103,7 @@ search_exception_table(const struct cpu_ =20 region =3D find_text_region(retptr); retptr =3D region && region->ex - ? search_one_extable(region->ex, region->ex_end - 1, retp= tr) + ? search_one_extable(region->ex, region->ex_end, retptr) : 0; if ( retptr ) { @@ -198,7 +199,7 @@ search_pre_exception_table(struct cpu_us { unsigned long addr =3D regs->rip; unsigned long fixup =3D search_one_extable( - __start___pre_ex_table, __stop___pre_ex_table-1, addr); + __start___pre_ex_table, __stop___pre_ex_table, addr); if ( fixup ) { dprintk(XENLOG_INFO, "Pre-exception: %p -> %p\n", _p(addr), _p(fix= up));