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      <blockquote type="cite">but how to understand 1)<br>
        <br>
        what do you mean "The CS can still be blocked because of
        amdgpu_ctx_add_fence()."<br>
      </blockquote>
      See amdgpu_ctx_add_fence(), it can block for previous command
      submissions just like entity_push_job(). So only moving
      entity_push_job() out of locking the PD doesn't help at all.<br>
      <br>
      <blockquote type="cite">for 2)The order of submission isn't
        correct any more.<br>
        <br>
        I think since the pointer "job" is already a dirty pointer,
        meaningless that  we talking about it if the order is correct
        ...<br>
      </blockquote>
      The problem isn't parser->job, but rather that the job is
      referencing the entity which is part of the context and we already
      called amdgpu_ctx_put() on that one.<br>
      <br>
      Regards,<br>
      Christian.<br>
      <br>
      Am 06.09.2017 um 10:04 schrieb Liu, Monk:<br>
    </div>
    <blockquote type="cite"
cite="mid:BLUPR12MB044977C621578CDB0427B52584970@BLUPR12MB0449.namprd12.prod.outlook.com">
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          <p>><font size="2"><span style="font-size:10pt">The patch
                doesn't work at all:<br>
                1. The CS can still be blocked because of
                amdgpu_ctx_add_fence().<br>
                2. The order of submission isn't correct any more.<br>
                3. We could end up using freed up memory because we now
                drop the<br>
                   ctx reference to early.</span></font></p>
          <p><font size="2"><span style="font-size:10pt"><br>
              </span></font></p>
          <p><font size="2"><span style="font-size:10pt">I suddenly
                found that the parser->job is really a wild pointer:</span></font></p>
          <p><font size="2"><span style="font-size:10pt"></span></font></p>
          <div style="color:#d4d4d4; background-color:#1e1e1e; font-family:'Droid Sans Mono','Courier New',monospace,'Droid Sans Fallback'; font-weight:normal; font-size:14px; line-height:19px; white-space:pre">
<div><span style="color:#d4d4d4">    </span><span style="color:#dcdcaa">amdgpu_cs_parser_fini</span><span style="color:#d4d4d4">(p,
</span><span style="color:#b5cea8">0</span><span style="color:#d4d4d4">, </span><span style="color:#569cd6">true</span><span style="color:#d4d4d4">);</span></div>


<div><span style="color:#d4d4d4">    </span><span style="color:#dcdcaa">trace_amdgpu_cs_ioctl</span><span style="color:#d4d4d4">(job);</span></div>
<div><span style="color:#d4d4d4">    </span><span style="color:#dcdcaa">amd_sched_entity_push_job</span><span style="color:#d4d4d4">(</span><span style="color:#d4d4d4">&</span><span style="color:#d4d4d4">job-></span><span style="color:#9cdcfe">base</span><span style="color:#d4d4d4">);</span></div>
</div>
          <p>so "cs_parser_fini" cannot be called before
            "entity_push_job", that part is correct</p>
          <p><br>
          </p>
          <p>but how to understand 1)<br>
          </p>
          <p><font size="2"><span style="font-size:10pt">what do you
                mean "The CS can still be blocked because of
                amdgpu_ctx_add_fence().</span></font>"</p>
          <p><br>
          </p>
          <p>for 2)<font size="2"><span style="font-size:10pt">The order
                of submission isn't correct any more.</span></font></p>
          <p>I think since the pointer "job" is already a dirty pointer,
            meaningless that  we talking about it if the order is
            correct ...
            <br>
          </p>
          <p><br>
          </p>
          <p>BR Monk<br>
          </p>
          <p><br>
          </p>
          <p><br>
          </p>
        </div>
        <hr tabindex="-1" style="display:inline-block; width:98%">
        <div id="x_divRplyFwdMsg" dir="ltr"><font style="font-size:11pt"
            face="Calibri, sans-serif" color="#000000"><b>From:</b>
            amd-gfx <a class="moz-txt-link-rfc2396E" href="mailto:amd-gfx-bounces@lists.freedesktop.org"><amd-gfx-bounces@lists.freedesktop.org></a> on
            behalf of Christian König <a class="moz-txt-link-rfc2396E" href="mailto:deathsimple@vodafone.de"><deathsimple@vodafone.de></a><br>
            <b>Sent:</b> Tuesday, September 5, 2017 9:14:23 PM<br>
            <b>To:</b> <a class="moz-txt-link-abbreviated" href="mailto:amd-gfx@lists.freedesktop.org">amd-gfx@lists.freedesktop.org</a>; Zhou,
            David(ChunMing)<br>
            <b>Subject:</b> [PATCH] drm/amdgpu: revert "fix deadlock of
            reservation between cs and gpu reset v2"</font>
          <div> </div>
        </div>
      </div>
      <font size="2"><span style="font-size:10pt;">
          <div class="PlainText">From: Christian König
            <a class="moz-txt-link-rfc2396E" href="mailto:christian.koenig@amd.com"><christian.koenig@amd.com></a><br>
            <br>
            This reverts commit
            10e709cb296c98424c03408d23e3addeddcd4088.<br>
            <br>
            The patch doesn't work at all:<br>
            1. The CS can still be blocked because of
            amdgpu_ctx_add_fence().<br>
            2. The order of submission isn't correct any more.<br>
            3. We could end up using freed up memory because we now drop
            the<br>
               ctx reference to early.<br>
            <br>
            This needs to be fixed cleanly by doing the context handling
            after the BO<br>
            handling, but this is a larger task just avoid the obvious
            crashes for now.<br>
            <br>
            Signed-off-by: Christian König
            <a class="moz-txt-link-rfc2396E" href="mailto:christian.koenig@amd.com"><christian.koenig@amd.com></a><br>
            ---<br>
             drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 4 ----<br>
             1 file changed, 4 deletions(-)<br>
            <br>
            diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
            b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c<br>
            index b96776c..2db4010 100644<br>
            --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c<br>
            +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c<br>
            @@ -1061,7 +1061,6 @@ static int amdgpu_cs_submit(struct
            amdgpu_cs_parser *p,<br>
                     cs->out.handle = amdgpu_ctx_add_fence(p->ctx,
            ring, p->fence);<br>
                     job->uf_sequence = cs->out.handle;<br>
                     amdgpu_job_free_resources(job);<br>
            -       amdgpu_cs_parser_fini(p, 0, true);<br>
             <br>
                     trace_amdgpu_cs_ioctl(job);<br>
                     amd_sched_entity_push_job(&job->base);<br>
            @@ -1120,10 +1119,7 @@ int amdgpu_cs_ioctl(struct drm_device
            *dev, void *data, struct drm_file *filp)<br>
                             goto out;<br>
             <br>
                     r = amdgpu_cs_submit(&parser, cs);<br>
            -       if (r)<br>
            -               goto out;<br>
             <br>
            -       return 0;<br>
             out:<br>
                     amdgpu_cs_parser_fini(&parser, r,
            reserved_buffers);<br>
                     return r;<br>
            -- <br>
            2.7.4<br>
            <br>
            _______________________________________________<br>
            amd-gfx mailing list<br>
            <a class="moz-txt-link-abbreviated" href="mailto:amd-gfx@lists.freedesktop.org">amd-gfx@lists.freedesktop.org</a><br>
            <a
              href="https://lists.freedesktop.org/mailman/listinfo/amd-gfx"
              moz-do-not-send="true">https://lists.freedesktop.org/mailman/listinfo/amd-gfx</a><br>
          </div>
        </span></font>
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      <br>
      <pre wrap="">_______________________________________________
amd-gfx mailing list
<a class="moz-txt-link-abbreviated" href="mailto:amd-gfx@lists.freedesktop.org">amd-gfx@lists.freedesktop.org</a>
<a class="moz-txt-link-freetext" href="https://lists.freedesktop.org/mailman/listinfo/amd-gfx">https://lists.freedesktop.org/mailman/listinfo/amd-gfx</a>
</pre>
    </blockquote>
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