From: Claudio Imbrenda Date: Tue, 23 Jun 2026 15:33:29 +0000 (+0200) Subject: KVM: s390: selftests: Fix cmma selftest X-Git-Tag: v7.2-rc1~30^2~2^2~1 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=125a3d3fac51571b8ede0d0599618c6ecd975ea8;p=thirdparty%2Flinux.git KVM: s390: selftests: Fix cmma selftest The existing cmma selftest depended on the host allocating page tables for all present memslots. Since the gmap rewrite, memory that is not accessed by the guest might not have page tables allocated yet. This caused the test to fail due to a mismatch in the assertion. Fix by having the guest access also the second half of the test memslot, thus guaranteeing that its page tables are present. Fixes: e38c884df921 ("KVM: s390: Switch to new gmap") Signed-off-by: Claudio Imbrenda Message-ID: <20260623153331.233784-9-imbrenda@linux.ibm.com> --- diff --git a/tools/testing/selftests/kvm/s390/cmma_test.c b/tools/testing/selftests/kvm/s390/cmma_test.c index e39a724fe860e..15d81b2ed7ad3 100644 --- a/tools/testing/selftests/kvm/s390/cmma_test.c +++ b/tools/testing/selftests/kvm/s390/cmma_test.c @@ -34,16 +34,22 @@ static char cmma_value_buf[MAIN_PAGE_COUNT + TEST_DATA_PAGE_COUNT]; /** * Dirty CMMA attributes of exactly one page in the TEST_DATA memslot, * so use_cmma goes on and the CMMA related ioctls do something. + * Touch the page at offset 1M inside TEST_DATA to make sure its page + * tables are allocated in the host. */ static void guest_do_one_essa(void) { asm volatile( /* load TEST_DATA_START_GFN into r1 */ + " xgr 1,1\n" " llilf 1,%[start_gfn]\n" /* calculate the address from the gfn */ " sllg 1,1,12(0)\n" /* set the first page in TEST_DATA memslot to STABLE */ " .insn rrf,0xb9ab0000,2,1,1,0\n" + " agfi 1,0x100000\n" + /* also touch the first page of the second MB of TEST_DATA */ + " .insn rrf,0xb9ab0000,2,1,1,0\n" /* hypercall */ " diag 0,0,0x501\n" "0: j 0b"