45 lines
1.7 KiB
Diff
45 lines
1.7 KiB
Diff
From 5dd9087fff74b5672526cad254e76f790fb35c7a Mon Sep 17 00:00:00 2001
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From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= <berrange@redhat.com>
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Date: Tue, 10 Jun 2025 13:37:03 +0100
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Subject: [PATCH] hw/ppc/spapr_tpm_proxy: skip automatic zero-init of large
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arrays
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MIME-Version: 1.0
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Content-Type: text/plain; charset=UTF-8
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Content-Transfer-Encoding: 8bit
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The 'tpm_execute' method has a pair of 4k arrays used for copying
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data between guest and host. Skip the automatic zero-init of these
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arrays to eliminate the performance overhead in the I/O hot path.
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The two arrays will be fully initialized when reading data from
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guest memory or reading data from the proxy FD.
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Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
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Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
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Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
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Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
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Message-id: 20250610123709.835102-26-berrange@redhat.com
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Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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---
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hw/ppc/spapr_tpm_proxy.c | 4 ++--
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1 file changed, 2 insertions(+), 2 deletions(-)
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diff --git a/hw/ppc/spapr_tpm_proxy.c b/hw/ppc/spapr_tpm_proxy.c
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index 862eeaa50a..1297b3ad56 100644
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--- a/hw/ppc/spapr_tpm_proxy.c
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+++ b/hw/ppc/spapr_tpm_proxy.c
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@@ -41,8 +41,8 @@ static ssize_t tpm_execute(SpaprTpmProxy *tpm_proxy, target_ulong *args)
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target_ulong data_in_size = args[2];
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uint64_t data_out = ppc64_phys_to_real(args[3]);
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target_ulong data_out_size = args[4];
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- uint8_t buf_in[TPM_SPAPR_BUFSIZE];
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- uint8_t buf_out[TPM_SPAPR_BUFSIZE];
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+ QEMU_UNINITIALIZED uint8_t buf_in[TPM_SPAPR_BUFSIZE];
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+ QEMU_UNINITIALIZED uint8_t buf_out[TPM_SPAPR_BUFSIZE];
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ssize_t ret;
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trace_spapr_tpm_execute(data_in, data_in_size, data_out, data_out_size);
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--
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2.47.3
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