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<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">Hi,
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">I’m trying to get satp mode on QEMU-USER, QEMU-SYSTEM and
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">hardware (HiFive Unmatched) by reading /proc/cpuinfo.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">Turns out we can only get mmu info on QEMU-SYSTEM and hardware.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">QEMU-USER will return empty string when reading /proc/cpuinfo.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">Any ideas about that?
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">Here are the outputs:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">QEMU-USER:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">$ /riscv-qemu/bin/qemu-riscv64 -L ~/riscv-sysroot/ release/images/jdk/bin/java -version<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">stap mode:
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">openjdk version "20" 2022-11-24<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">OpenJDK Runtime Environment OpenJDK (build 20)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">OpenJDK 64-Bit Server VM OpenJDK (build 20, mixed mode)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">QEMU-SYSTEM
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">[root@fedora-riscv ~]# jdk-satp/bin/java -version<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">vm_mode: sv48<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">stap mode: sv48<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">openjdk version "20" 2022-11-24<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">OpenJDK Runtime Environment OpenJDK (build 20)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">OpenJDK 64-Bit Server VM OpenJDK (build 20, mixed mode)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">HiFive Unmatched:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">$ jdk-satp/bin/java -version<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">vm_mode: sv39<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">uarch: sifive,u74-mc<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">stap mode: sv39<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">openjdk version "20" 2022-11-24<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">OpenJDK Runtime Environment OpenJDK (build 20)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif">OpenJDK 64-Bit Server VM OpenJDK (build 20, mixed mode)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> riscv-port-dev <riscv-port-dev-retn@openjdk.org>
<b>On Behalf Of </b>yangfei@iscas.ac.cn<br>
<b>Sent:</b> Thursday, November 24, 2022 6:16 PM<br>
<b>To:</b> Ludovic Henry <ludovic@rivosinc.com><br>
<b>Cc:</b> Vladimir Kempik <vladimir.kempik@gmail.com>; Zixian Cai <zixian.cai@anu.edu.au>; riscv-port-dev@openjdk.org; Ze Zhang <zhangze.linux@gmail.com><br>
<b>Subject:</b> Re: Re: openjdk 20 crash on linux kernel 5.19, because it can not support huge VM?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I think at this stage we should do some detection for sv57+ at JVM startup time and explicitly issue a warning and stop early. <o:p></o:p></span></p>
<p><span lang="EN-US">That would be better and more elegant than simply crashing the JVM afterwards.
<o:p></o:p></span></p>
<p><span lang="EN-US">I see this kind of information is availble on linux-riscv64 at /proc/cpuinfo:
<o:p></o:p></span></p>
<p><span lang="EN-US"><o:p> </o:p></span></p>
<p><span lang="EN-US">$ cat /proc/cpuinfo<br>
processor : 0<br>
hart : 1<br>
isa : rv64imafdc<br>
mmu : sv39<br>
uarch : sifive,u74-mc<o:p></o:p></span></p>
<p><span lang="EN-US">Regards, <o:p></o:p></span></p>
<p><span lang="EN-US">Fei <o:p></o:p></span></p>
<blockquote style="border:none;border-left:solid #B6B6B6 1.5pt;padding:0cm 0cm 0cm 4.0pt;margin-left:3.75pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt" name="replyContent">
<p class="MsoNormal" style="margin-bottom:12.0pt"><span lang="EN-US">-----Original Messages-----<br>
<b>From:</b>"Ludovic Henry" <<a href="mailto:ludovic@rivosinc.com">ludovic@rivosinc.com</a>><br>
<b>Sent Time:</b>2022-11-24 07:25:19 (Thursday)<br>
<b>To:</b> "Vladimir Kempik" <<a href="mailto:vladimir.kempik@gmail.com">vladimir.kempik@gmail.com</a>><br>
<b>Cc:</b> "Zixian Cai" <<a href="mailto:zixian.cai@anu.edu.au">zixian.cai@anu.edu.au</a>>, "<a href="mailto:riscv-port-dev@openjdk.org">riscv-port-dev@openjdk.org</a>" <<a href="mailto:riscv-port-dev@openjdk.org">riscv-port-dev@openjdk.org</a>>, "Ze Zhang"
<<a href="mailto:zhangze.linux@gmail.com">zhangze.linux@gmail.com</a>><br>
<b>Subject:</b> Re: openjdk 20 crash on linux kernel 5.19, because it can not support huge VM?<o:p></o:p></span></p>
<div>
<p class="MsoNormal"><span lang="EN-US">Hi, <o:p></o:p></span></p>
<div>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US">We are currently working on contributing to Qemu a command-line option to disable/enable certain modes in Qemu. I'll keep you posted as soon as I've anything material to share.
<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US">The solution on the OpenJDK should IMO to probe at startup for the satp mode (sv39/sv48/sv57/sv64) and generate the appropriate and cheapest movptr according to this value. I wouldn't want to pay the full cost of sv57
or sv64 while no existing boards or hardware even support anything more than sv48. Especially given the current discussions in RISC-V on reducing the cost of auipc/jalr, movptr, and trampolines.
<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US">Thanks, <o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US">Ludovic <o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<div>
<div>
<p class="MsoNormal"><span lang="EN-US">On Wed, Nov 23, 2022 at 9:33 AM Vladimir Kempik <<a href="mailto:vladimir.kempik@gmail.com">vladimir.kempik@gmail.com</a>> wrote:<o:p></o:p></span></p>
</div>
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<div>
<p class="MsoNormal"><span lang="EN-US">Hello <o:p></o:p></span></p>
<div>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US">A kind of workaround for this case <o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US">disable sv57 csr and rebuild qemu - <a href="https://github.com/qemu/qemu/blob/master/target/riscv/csr.c#L1027" target="_blank">https://github.com/qemu/qemu/blob/master/target/riscv/csr.c#L1027</a> put 0 here
<o:p></o:p></span></p>
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<div>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US">Regards, Vladimir<o:p></o:p></span></p>
<div>
<p class="MsoNormal"><span lang="EN-US"><br>
<br>
<o:p></o:p></span></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<div>
<p class="MsoNormal"><span lang="EN-US">23 </span>нояб<span lang="EN-US">. 2022 </span>
г<span lang="EN-US">., </span>в<span lang="EN-US"> 04:08, Zixian Cai <<a href="mailto:zixian.cai@anu.edu.au" target="_blank">zixian.cai@anu.edu.au</a>>
</span>написал<span lang="EN-US">(</span>а<span lang="EN-US">): <o:p></o:p></span></p>
</div>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<div>
<div>
<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">This has been discussed in a previous thread. </span><span lang="EN-US"><a href="https://mail.openjdk.org/pipermail/riscv-port-dev/2022-September/000636.html" target="_blank"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">https://mail.openjdk.org/pipermail/riscv-port-dev/2022-September/000636.html</span></a></span><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">I agree that it would be nice to support different modes. Although with the patches in QEMU/Kernel that can restrict the OS to run with sv39/sv48 only, and the
fact that there are not enough real hardware board supporting above sv48, I don’t know whether there will be sufficient motivation to fix the problem in the short term.
<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">Also worth noting until very recently (Intel implemented 5-level paging around the release of Ice Lake), x86_64 has been staying 48 bits a for long time.
<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">Sincerely,
<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">Zixian
<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">On 23/11/2022, 11:58, "riscv-port-dev" <</span><span lang="EN-US"><a href="mailto:riscv-port-dev-retn@openjdk.org" target="_blank"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">riscv-port-dev-retn@openjdk.org</span></a></span><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">>
wrote: <o:p></o:p></span></p>
<div>
<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">hi,
<o:p></o:p></span></p>
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<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> openjdk 20 crash on linux kernel 5.19, because it can not support huge VM?
<o:p></o:p></span></p>
</div>
</div>
<div>
<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">but I think openjdk as a application, it should not has any limitation on virtual address length,
<o:p></o:p></span></p>
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<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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<div>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">even if it has very close relationship with hardware, just as qemu should not depend on hardware VM size, it's none of business for an application, because all
other apps can run very well. <o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">when will it support the newest kernel and qemu?
<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US"><a href="https://groups.google.com/a/groups.riscv.org/g/sw-dev/c/pILY0WGHhOs" target="_blank"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">https://groups.google.com/a/groups.riscv.org/g/sw-dev/c/pILY0WGHhOs</span></a></span><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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