From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:49028) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QSSmI-0006NV-4Y for qemu-devel@nongnu.org; Fri, 03 Jun 2011 07:43:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QSSmB-0001E7-UG for qemu-devel@nongnu.org; Fri, 03 Jun 2011 07:42:57 -0400 Received: from cantor.suse.de ([195.135.220.2]:36430 helo=mx1.suse.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QSSmA-0001Cq-Lc for qemu-devel@nongnu.org; Fri, 03 Jun 2011 07:42:50 -0400 From: Alexander Graf Date: Thu, 2 Jun 2011 08:51:42 +0200 Message-Id: <1306997503-29304-13-git-send-email-agraf@suse.de> In-Reply-To: <1306997503-29304-1-git-send-email-agraf@suse.de> References: <1306997503-29304-1-git-send-email-agraf@suse.de> Subject: [Qemu-devel] [PATCH 12/13] s390x: fix cksm instruction List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "qemu-devel@nongnu.org Developers" Cc: Aurelien Jarno The cksm instruction was implemented incorrectly, rendering UDP and TCP checksum calculation wrong, making an emulated s390x Linux guest break in most networking operations. This patch fixes odd end checksum calculation, takes the input register as input for the checksum and optimizes the overflow pieces by a bit. Signed-off-by: Alexander Graf --- target-s390x/op_helper.c | 28 ++++++++-------------------- 1 files changed, 8 insertions(+), 20 deletions(-) diff --git a/target-s390x/op_helper.c b/target-s390x/op_helper.c index 49760a4..db03a79 100644 --- a/target-s390x/op_helper.c +++ b/target-s390x/op_helper.c @@ -1731,25 +1731,15 @@ void HELPER(sqdbr)(uint32_t f1, uint32_t f2) env->fregs[f1].d = float64_sqrt(env->fregs[f2].d, &env->fpu_status); } -static inline uint64_t cksm_overflow(uint64_t cksm) -{ - if (cksm > 0xffffffffULL) { - cksm &= 0xffffffffULL; - cksm++; - } - return cksm; -} - /* checksum */ void HELPER(cksm)(uint32_t r1, uint32_t r2) { uint64_t src = get_address_31fix(r2); uint64_t src_len = env->regs[(r2 + 1) & 15]; - uint64_t cksm = 0; + uint64_t cksm = (uint32_t)env->regs[r1]; while (src_len >= 4) { cksm += ldl(src); - cksm = cksm_overflow(cksm); /* move to next word */ src_len -= 4; @@ -1760,26 +1750,24 @@ void HELPER(cksm)(uint32_t r1, uint32_t r2) case 0: break; case 1: - cksm += ldub(src); - cksm = cksm_overflow(cksm); + cksm += ldub(src) << 24; break; case 2: - cksm += lduw(src); - cksm = cksm_overflow(cksm); + cksm += lduw(src) << 16; break; case 3: - /* XXX check if this really is correct */ - cksm += lduw(src) << 8; - cksm += ldub(src + 2); - cksm = cksm_overflow(cksm); + cksm += lduw(src) << 16; + cksm += ldub(src + 2) << 8; break; } /* indicate we've processed everything */ + env->regs[r2] = src + src_len; env->regs[(r2 + 1) & 15] = 0; /* store result */ - env->regs[r1] = (env->regs[r1] & 0xffffffff00000000ULL) | (uint32_t)cksm; + env->regs[r1] = (env->regs[r1] & 0xffffffff00000000ULL) | + ((uint32_t)cksm + (cksm >> 32)); } static inline uint32_t cc_calc_ltgt_32(CPUState *env, int32_t src, -- 1.6.0.2