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Tsirkin" , Peter Maydell , qemu-block@nongnu.org, Stefan Hajnoczi , Kevin Wolf References: <20250610123709.835102-1-berrange@redhat.com> <20250610123709.835102-26-berrange@redhat.com> Content-Language: en-US From: Harsh Prateek Bora In-Reply-To: <20250610123709.835102-26-berrange@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=Pfr/hjhd c=1 sm=1 tr=0 ts=68494a7d cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=IkcTkHD0fZMA:10 a=6IFa9wvqVegA:10 a=f7IdgyKtn90A:10 a=20KFwNOVAAAA:8 a=VnNF1IyMAAAA:8 a=RGSA8qlED6iX_nMAe8wA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: BVpNZqKzhHuT8gDDcD2XJXTduJf4YAlc X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNjExMDA3OSBTYWx0ZWRfX7vLlniUZIxk4 mGO5vmnhv94fKge6bVyBQFk5rtE8oTlcntTvnC7bR6ejnkik1b/nqIWLRruJLw2M77Ryr/Y+lQF gu9DX1oeLv0Gz6lxPBLf78crbTiiQSH9io0+Rsg4XcHjr34lmWCcs8Num6zaAvX5FNib5u/eus8 LAx/MzkaTqKoY/flbV/BliHbCVz4I19FaT4+4dxhVPNEe1G5tf5EXNYhvp7xqA3/lCHiI1nO3vt mT6CwtLmBAOPZwdXYLRmuTBGio400JDj/vWKJFTl51nQznEAaF6lQlxKsic9U+Bx6Tqvg7hBx3r B04lj0fV4SPcI7uM2vYBwJ3+4zJpPXYSogwdYcKBIsGjuKjAINtJCZS0+9faLsXXs8kiMNsOxIk jSjDBjZbQ8gMWdsuT5B1VQTNQuSWTJUoPs8iAsNwdABDcuZco+7fU9e+vMpFNoTFDc6qeBgP X-Proofpoint-ORIG-GUID: BVpNZqKzhHuT8gDDcD2XJXTduJf4YAlc X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.0.736,FMLib:17.12.80.40 definitions=2025-06-11_03,2025-06-10_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 priorityscore=1501 impostorscore=0 suspectscore=0 adultscore=0 clxscore=1015 phishscore=0 bulkscore=0 malwarescore=0 mlxlogscore=828 mlxscore=0 lowpriorityscore=0 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2505280000 definitions=main-2506110079 Received-SPF: pass client-ip=148.163.158.5; envelope-from=harshpb@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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, 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: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 6/10/25 18:07, Daniel P. Berrangé wrote: > The 'tpm_execute' method has a pair of 4k arrays used for copying > data between guest and host. Skip the automatic zero-init of these > arrays to eliminate the performance overhead in the I/O hot path. > > The two arrays will be fully initialized when reading data from > guest memory or reading data from the proxy FD. > > Signed-off-by: Daniel P. Berrangé > --- > hw/ppc/spapr_tpm_proxy.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/hw/ppc/spapr_tpm_proxy.c b/hw/ppc/spapr_tpm_proxy.c > index 862eeaa50a..1297b3ad56 100644 > --- a/hw/ppc/spapr_tpm_proxy.c > +++ b/hw/ppc/spapr_tpm_proxy.c > @@ -41,8 +41,8 @@ static ssize_t tpm_execute(SpaprTpmProxy *tpm_proxy, target_ulong *args) > target_ulong data_in_size = args[2]; > uint64_t data_out = ppc64_phys_to_real(args[3]); > target_ulong data_out_size = args[4]; > - uint8_t buf_in[TPM_SPAPR_BUFSIZE]; > - uint8_t buf_out[TPM_SPAPR_BUFSIZE]; > + QEMU_UNINITIALIZED uint8_t buf_in[TPM_SPAPR_BUFSIZE]; > + QEMU_UNINITIALIZED uint8_t buf_out[TPM_SPAPR_BUFSIZE]; Reviewed-by: Harsh Prateek Bora > ssize_t ret; > > trace_spapr_tpm_execute(data_in, data_in_size, data_out, data_out_size);