| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (C) 2021 ARM Limited |
| * |
| * Attempt to change the SVE vector length in a signal hander, this is not |
| * supported and is expected to segfault. |
| */ |
| |
| #include <kselftest.h> |
| #include <signal.h> |
| #include <ucontext.h> |
| #include <sys/prctl.h> |
| |
| #include "test_signals_utils.h" |
| #include "testcases.h" |
| |
| struct fake_sigframe sf; |
| static unsigned int vls[SVE_VQ_MAX]; |
| unsigned int nvls = 0; |
| |
| static bool sve_get_vls(struct tdescr *td) |
| { |
| int vq, vl; |
| |
| /* |
| * Enumerate up to SVE_VQ_MAX vector lengths |
| */ |
| for (vq = SVE_VQ_MAX; vq > 0; --vq) { |
| vl = prctl(PR_SVE_SET_VL, vq * 16); |
| if (vl == -1) |
| return false; |
| |
| vl &= PR_SVE_VL_LEN_MASK; |
| |
| /* Skip missing VLs */ |
| vq = sve_vq_from_vl(vl); |
| |
| vls[nvls++] = vl; |
| } |
| |
| /* We need at least two VLs */ |
| if (nvls < 2) { |
| fprintf(stderr, "Only %d VL supported\n", nvls); |
| td->result = KSFT_SKIP; |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static int fake_sigreturn_sve_change_vl(struct tdescr *td, |
| siginfo_t *si, ucontext_t *uc) |
| { |
| size_t resv_sz, offset; |
| struct _aarch64_ctx *head = GET_SF_RESV_HEAD(sf); |
| struct sve_context *sve; |
| |
| /* Get a signal context with a SVE frame in it */ |
| if (!get_current_context(td, &sf.uc, sizeof(sf.uc))) |
| return 1; |
| |
| resv_sz = GET_SF_RESV_SIZE(sf); |
| head = get_header(head, SVE_MAGIC, resv_sz, &offset); |
| if (!head) { |
| fprintf(stderr, "No SVE context\n"); |
| return 1; |
| } |
| |
| if (head->size != sizeof(struct sve_context)) { |
| fprintf(stderr, "SVE register state active, skipping\n"); |
| return 1; |
| } |
| |
| sve = (struct sve_context *)head; |
| |
| /* No changes are supported; init left us at minimum VL so go to max */ |
| fprintf(stderr, "Attempting to change VL from %d to %d\n", |
| sve->vl, vls[0]); |
| sve->vl = vls[0]; |
| |
| fake_sigreturn(&sf, sizeof(sf), 0); |
| |
| return 1; |
| } |
| |
| struct tdescr tde = { |
| .name = "FAKE_SIGRETURN_SVE_CHANGE", |
| .descr = "Attempt to change SVE VL", |
| .feats_required = FEAT_SVE, |
| .sig_ok = SIGSEGV, |
| .timeout = 3, |
| .init = sve_get_vls, |
| .run = fake_sigreturn_sve_change_vl, |
| }; |