From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8A7EAC4453A for ; Wed, 22 Jul 2026 09:31:17 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wmTHr-0002Nm-MA; Wed, 22 Jul 2026 05:30:47 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wmTHp-0002Hh-HS; Wed, 22 Jul 2026 05:30:45 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wmTHn-00068Y-Ex; Wed, 22 Jul 2026 05:30:45 -0400 Received: from pps.filterd (m0360072.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 66M9CMNZ3672791; Wed, 22 Jul 2026 09:30:32 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:reply-to:subject:to; s=pp1; bh=hK4lvS/eGvsFDNHxzzMPSM81TFxBfsX/YW67RrJBjA4=; b=QB7d7qEvt/Rd hxqb03/7PEzrgM8kDnJBeZk3AGzphbC2LgEb/AZJP3/pZmxFAXoynu4lJN0YT0JY wnyrWPIfWt1emOAm1F50wmatWMaqeBFw71mK1vXum4ApLRNhOBojLbbSLPmtZ1zq 7uJEbt4hdRWIlHEgD/IjcCwqcM+2ZOf60SWqKrrzW4mChDNQ2P7DpS8bvNsQI0aK F18qiwFka+Hqp5zryzLV5eUYOPXkiKIj1sbj2TprudwHIy04qtR2fAl2JvzWHKAs xGaC0uMC+sJ6sKTYXF1Rw4h8S/9me1drIRJ7Ev6hbo8tuAnFMas6wOfIDIDnJWUG ttaSEZALhA== Received: from ppma21.wdc07v.mail.ibm.com (5b.69.3da9.ip4.static.sl-reverse.com [169.61.105.91]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4fg7ah8wbv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 Jul 2026 09:30:31 +0000 (GMT) Received: from pps.filterd (ppma21.wdc07v.mail.ibm.com [127.0.0.1]) by ppma21.wdc07v.mail.ibm.com (8.18.1.7/8.18.1.7) with ESMTP id 66M9Jhxw016054; Wed, 22 Jul 2026 09:30:31 GMT Received: from smtprelay02.dal12v.mail.ibm.com ([172.16.1.4]) by ppma21.wdc07v.mail.ibm.com (PPS) with ESMTPS id 4fgmtjxmjw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 Jul 2026 09:30:31 +0000 (GMT) Received: from smtpav02.dal12v.mail.ibm.com (smtpav02.dal12v.mail.ibm.com [10.241.53.101]) by smtprelay02.dal12v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 66M9UUGx57016702 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 22 Jul 2026 09:30:30 GMT Received: from smtpav02.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F32545805F; Wed, 22 Jul 2026 09:30:29 +0000 (GMT) Received: from smtpav02.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7648D58051; Wed, 22 Jul 2026 09:30:29 +0000 (GMT) Received: from ltc.linux.ibm.com (unknown [9.5.196.140]) by smtpav02.dal12v.mail.ibm.com (Postfix) with ESMTP; Wed, 22 Jul 2026 09:30:29 +0000 (GMT) MIME-Version: 1.0 Date: Wed, 22 Jul 2026 11:30:29 +0200 From: Harald Freudenberger To: Ilya Leoshkevich Cc: Richard Henderson , Cornelia Huck , Eric Farman , Matthew Rosato , David Hildenbrand , qemu-s390x@nongnu.org, qemu-devel@nongnu.org, Christian Borntraeger , qemu-stable@nongnu.org Subject: Re: [PATCH v2 1/2] target/s390x: Make PRNO TRNG interruptible Mail-Reply-To: freude@linux.ibm.com In-Reply-To: <20260714191948.342204-2-iii@linux.ibm.com> References: <20260714191948.342204-1-iii@linux.ibm.com> <20260714191948.342204-2-iii@linux.ibm.com> Message-ID: X-Sender: freude@linux.ibm.com Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: 3g1Tg3kM86sionZqogh46cmEU87y7iPx X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNzIyMDA4NyBTYWx0ZWRfX1FSe8XI6Kln6 4dnAgplGmGFhP+hRPoC1dvj4qhC1ov6qwRWgwFzuCOwxclF7NztdSCj9vfgEkfDsqgOXPVtHW4p YP7MoCn3f15EOngmUbqvuulOcWwMYmtXRHdH7eb+PYFMlTo//rE6DlQ6qNjGZ2QnNyE1CHsco6d 0dOVO+YTYdWfO0ZFrBkJwt4WwiCeIVBcuV/EXay01/vaZWa6QfdH+q8+TEVbLgBPW2pQyQbrPvI ldFmbuZkj3W2dqsrrJQlt5e6W3ehMv1gvvrSrmTK6dWUtC/f40gYI4JGIPV2bSVyquQnkoz5W+A V+OOtznpk0k6llupK9hAs31TuNLWcY7U2ULqd0VwaDeijF4dUYHGjbTPLWjIunZatcqdIUninIL mK1ipUroew/c2phs+nFSANtz95zFT5e9KCD7Z4IZ9IX3msNpC6OQ7HF8rhQYUX59AHqVQNKpnY8 l+MD1d4f67TOLD2ztRA== X-Proofpoint-Spam-Info: AW1haW4tMjYwNzIyMDA4NyBTYWx0ZWRfXxe7uaNjObl9r xhfIQp/UyDhnLrxNQW2VVuHOd8iFxr2a47Pc7gBttjYQxcReru4GbQeSfYC67u9ypU/xoNhuh+j J5zZ63iqnuwZc8FNZ5tjHOlU/PfF9xw= X-Proofpoint-GUID: 3g1Tg3kM86sionZqogh46cmEU87y7iPx X-Authority-Analysis: v=2.4 cv=SM5ykuvH c=1 sm=1 tr=0 ts=6a608db7 cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=kj9zAlcOel0A:10 a=RAioF0-LDSMA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=RzCfie-kr_QcCd8fBx8p:22 a=VnNF1IyMAAAA:8 a=69wJf7TsAAAA:8 a=KKAkSRfTAAAA:8 a=j-UDTZna37xY2s4fqbMA:9 a=CjuIK1q_8ugA:10 a=Fg1AiH1G6rFz08G2ETeA:22 a=cvBusfyB2V15izCimMoJ:22 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-07-22_03,2026-07-21_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 lowpriorityscore=0 bulkscore=0 suspectscore=0 adultscore=0 spamscore=0 malwarescore=0 priorityscore=1501 phishscore=0 impostorscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2607220087 Received-SPF: pass client-ip=148.163.158.5; envelope-from=freude@linux.ibm.com; helo=mx0b-001b2d01.pphosted.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: freude@linux.ibm.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 2026-07-14 21:17, Ilya Leoshkevich wrote: > fill_buf_random() writes the entire guest-requested amount of random > bytes in one go. Since the length is a full 64-bit value, a guest can > request several gigabytes and keep the vCPU spinning inside the helper, > without a chance to react to interrupts. > > Do the same thing as HELPER(mvcl): check cpu_loop_exit_requested() at > the > bottom of the loop, and when a return to the main loop is pending, stop > and report partial completion with condition code 3. > > Reported-by: Christian Borntraeger > Fixes: 3dbc5fdacb5a ("target/s390x: support PRNO_TRNG instruction") > Cc: qemu-stable@nongnu.org > Reviewed-by: Richard Henderson > Signed-off-by: Ilya Leoshkevich > --- > target/s390x/tcg/crypto_helper.c | 22 +++++++++++++++++----- > 1 file changed, 17 insertions(+), 5 deletions(-) > > diff --git a/target/s390x/tcg/crypto_helper.c > b/target/s390x/tcg/crypto_helper.c > index 8fe0a222198..6a5dbe1cafa 100644 > --- a/target/s390x/tcg/crypto_helper.c > +++ b/target/s390x/tcg/crypto_helper.c > @@ -16,6 +16,7 @@ > #include "qemu/guest-random.h" > #include "s390x-internal.h" > #include "tcg_s390x.h" > +#include "exec/cpu-common.h" > #include "exec/helper-proto.h" > #include "accel/tcg/cpu-ldst-common.h" > #include "accel/tcg/cpu-mmu-index.h" > @@ -242,8 +243,8 @@ static int cpacf_sha512(CPUS390XState *env, const > int mmu_idx, uintptr_t ra, > return !len ? 0 : 3; > } > > -static void fill_buf_random(CPUS390XState *env, const int mmu_idx, > uintptr_t ra, > - uint64_t *buf_reg, uint64_t *len_reg) > +static int fill_buf_random(CPUS390XState *env, const int mmu_idx, > uintptr_t ra, > + uint64_t *buf_reg, uint64_t *len_reg) > { > const MemOpIdx oi = make_memop_idx(MO_8, mmu_idx); > uint8_t tmp[256]; > @@ -265,7 +266,13 @@ static void fill_buf_random(CPUS390XState *env, > const int mmu_idx, uintptr_t ra, > --*len_reg; > } > len -= block; > + > + if (cpu_loop_exit_requested(env_cpu(env))) { > + break; > + } > } > + > + return len == 0 ? 0 : 3; > } > > uint32_t HELPER(msa)(CPUS390XState *env, uint32_t r1, uint32_t r2, > uint32_t r3, > @@ -278,6 +285,7 @@ uint32_t HELPER(msa)(CPUS390XState *env, uint32_t > r1, uint32_t r2, uint32_t r3, > uint8_t subfunc[16] = { 0 }; > uint64_t param_addr; > MemOpIdx oi; > + int cc; > > switch (type) { > case S390_FEAT_TYPE_KMAC: > @@ -308,9 +316,13 @@ uint32_t HELPER(msa)(CPUS390XState *env, uint32_t > r1, uint32_t r2, uint32_t r3, > return cpacf_sha512(env, mmu_idx, ra, env->regs[1], > &env->regs[r2], > &env->regs[r2 + 1], type); > case 114: /* CPACF_PRNO_TRNG */ > - fill_buf_random(env, mmu_idx, ra, &env->regs[r1], > &env->regs[r1 + 1]); > - fill_buf_random(env, mmu_idx, ra, &env->regs[r2], > &env->regs[r2 + 1]); > - break; > + cc = fill_buf_random(env, mmu_idx, ra, > + &env->regs[r1], &env->regs[r1 + 1]); > + if (cc == 0) { > + cc = fill_buf_random(env, mmu_idx, ra, > + &env->regs[r2], &env->regs[r2 + 1]); > + } > + return cc; > default: > /* we don't implement any other subfunction yet */ > g_assert_not_reached(); Reviewed-by: Harald Freudenberger