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Internal Use Only<br>
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Hello,</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
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<div class="elementToProof"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">for reading usermode addresses on arm64, bpftrace needs the newer bpf_probe_read_user()
helper, while on x86_64 the older </span><span style="letter-spacing: normal; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 16px; font-weight: 400; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">bpf_probe_read()
helper works for both user and kernel addresses.</span></div>
<div class="elementToProof"><span style="letter-spacing: normal; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 16px; font-weight: 400; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);"><br>
</span></div>
<div class="elementToProof"><span style="letter-spacing: normal; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 16px; font-weight: 400; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">bpf_probe_read_user()
is available since linux-5.5, and was backported to Ubuntu 5.4-azure kernels in 2022:</span></div>
<div class="elementToProof"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"><br>
</span></div>
<div class="elementToProof"><span style="letter-spacing: normal; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 16px; font-weight: 400; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">Can
the same patch be applied to 5.4-generic kernels as well ? </span></div>
<div class="elementToProof"><span style="letter-spacing: normal; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 16px; font-weight: 400; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);"><br>
</span></div>
<div class="elementToProof"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">kernel-team [PATCH] thread with details:</span></div>
<div class="elementToProof"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"><a href="https://lists.ubuntu.com/archives/kernel-team/2022-September/133038.html" id="LPlnk608386">https://lists.ubuntu.com/archives/kernel-team/2022-September/133038.html</a></span></div>
<div class="elementToProof"><br>
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<div class="elementToProof"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">Launchpad bug for this fix:</span></div>
<div class="elementToProof"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"><a href="https://bugs.launchpad.net/ubuntu/+source/linux-azure/+bug/1990009" id="LPlnk555305">https://bugs.launchpad.net/ubuntu/+source/linux-azure/+bug/1990009</a></span></div>
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<br>
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<div class="elementToProof"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">Thanks,</span></div>
<div class="elementToProof"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">Bogdan</span></div>
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