From: Jordan Niethe Date: Mon, 24 Aug 2020 13:12:31 +0000 (+1000) Subject: selftests/powerpc: Fix prefixes in alignment_handler signal handler X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=db96221a683342fd4775fd820a4d5376cd2f2ed0;p=linux.git selftests/powerpc: Fix prefixes in alignment_handler signal handler The signal handler in the alignment handler self test has the ability to jump over the instruction that triggered the signal. It does this by incrementing the PT_NIP in the user context by 4. If it were a prefixed instruction this will mean that the suffix is then executed which is incorrect. Instead check if the major opcode indicates a prefixed instruction (e.g. it is 1) and if so increment PT_NIP by 8. If ISA v3.1 is not available treat it as a word instruction even if the major opcode is 1. Fixes: 620a6473df36 ("selftests/powerpc: Add prefixed loads/stores to alignment_handler test") Signed-off-by: Jordan Niethe [mpe: Fix 32-bit build, rename haveprefixes to prefixes_enabled] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200824131231.14008-1-jniethe5@gmail.com --- diff --git a/tools/testing/selftests/powerpc/alignment/alignment_handler.c b/tools/testing/selftests/powerpc/alignment/alignment_handler.c index e4063eba4a5bc..2a0503bc7e492 100644 --- a/tools/testing/selftests/powerpc/alignment/alignment_handler.c +++ b/tools/testing/selftests/powerpc/alignment/alignment_handler.c @@ -62,6 +62,7 @@ int bufsize; int debug; int testing; volatile int gotsig; +bool prefixes_enabled; char *cipath = "/dev/fb0"; long cioffset; @@ -75,7 +76,12 @@ void sighandler(int sig, siginfo_t *info, void *ctx) } gotsig = sig; #ifdef __powerpc64__ - ucp->uc_mcontext.gp_regs[PT_NIP] += 4; + if (prefixes_enabled) { + u32 inst = *(u32 *)ucp->uc_mcontext.gp_regs[PT_NIP]; + ucp->uc_mcontext.gp_regs[PT_NIP] += ((inst >> 26 == 1) ? 8 : 4); + } else { + ucp->uc_mcontext.gp_regs[PT_NIP] += 4; + } #else ucp->uc_mcontext.uc_regs->gregs[PT_NIP] += 4; #endif @@ -646,6 +652,8 @@ int main(int argc, char *argv[]) exit(1); } + prefixes_enabled = have_hwcap2(PPC_FEATURE2_ARCH_3_1); + rc |= test_harness(test_alignment_handler_vsx_206, "test_alignment_handler_vsx_206"); rc |= test_harness(test_alignment_handler_vsx_207,