<html><head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> </head> <body> <p><br> </p> <div class="moz-cite-prefix">On 2021-09-01 9:45 a.m., Kim, Jonathan wrote:<br> </div> <blockquote type="cite" cite="mid:DM5PR12MB4680D1A4C08DBD7DCF72120985CD9@DM5PR12MB4680.namprd12.prod.outlook.com"> <meta name="Generator" content="Microsoft Word 15 (filtered medium)"> <style>@font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4;}@font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4;}@font-face {font-family:"Malgun Gothic"; panose-1:2 11 5 3 2 0 0 2 0 4;}@font-face {font-family:Consolas; panose-1:2 11 6 9 2 2 4 3 2 4;}@font-face {font-family:"\@Malgun Gothic"; panose-1:2 11 5 3 2 0 0 2 0 4;}p.MsoNormal, li.MsoNormal, div.MsoNormal {margin:0in; font-size:11.0pt; font-family:"Calibri",sans-serif;}a:link, span.MsoHyperlink {mso-style-priority:99; color:blue; text-decoration:underline;}pre {mso-style-priority:99; mso-style-link:"HTML Preformatted Char"; margin:0in; font-size:10.0pt; font-family:"Courier New";}span.HTMLPreformattedChar {mso-style-name:"HTML Preformatted Char"; mso-style-priority:99; mso-style-link:"HTML Preformatted"; font-family:"Consolas",serif;}span.EmailStyle21 {mso-style-type:personal-reply; font-family:"Calibri",sans-serif; color:windowtext;}.MsoChpDefault {mso-style-type:export-only; font-size:10.0pt;}div.WordSection1 {page:WordSection1;}</style> <p style="font-family:Arial;font-size:10pt;color:#0000FF;margin:5pt;" align="Left"> [AMD Official Use Only]<br> </p> <br> <div> <div class="WordSection1"> <p class="MsoNormal">We were seeing process leaks on a couple of machines running certain tests that triggered vm faults on purpose.<o:p></o:p></p> <p class="MsoNormal">I think svm_range_restore_pages gets called unconditionally on vm fault handling (unless the retry interrupt payload bit is supposed to be clear with xnack off)?<o:p></o:p></p> <p class="MsoNormal"><o:p> </o:p></p> </div> </div> </blockquote> <p>yes, with xnack off, sh_mem_config retry should be off, retry bit is supposed to be clear in fault interrupt vector, we should not try to recover vm fault, just report the vm fault back to application and evict user queues. Maybe it is another bug cause p->xnack_enabled and sh_mem_config retry mismatch under specific condition?<br> </p> <p>Regards,</p> <p>Philip<br> </p> <blockquote type="cite" cite="mid:DM5PR12MB4680D1A4C08DBD7DCF72120985CD9@DM5PR12MB4680.namprd12.prod.outlook.com"> <div> <div class="WordSection1"> <p class="MsoNormal">Either way, this patch prevents the process leaks we seeing and is also:<o:p></o:p></p> <p class="MsoNormal">Reviewed-by: Jonathan Kim <a class="moz-txt-link-rfc2396E" href="mailto:jonathan.kim@amd.com"><jonathan.kim@amd.com></a><o:p></o:p></p> <p class="MsoNormal"><o:p> </o:p></p> <p class="MsoNormal">Thanks,<o:p></o:p></p> <p class="MsoNormal"><o:p> </o:p></p> <p class="MsoNormal">Jon<o:p></o:p></p> <p class="MsoNormal"><o:p> </o:p></p> <p class="MsoNormal"><o:p> </o:p></p> <div style="border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt"> <div> <div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in"> <p class="MsoNormal"><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> <b>On Behalf Of </b>philip yang<br> <b>Sent:</b> Wednesday, September 1, 2021 7:30 AM<br> <b>To:</b> Sierra Guiza, Alejandro (Alex) <a class="moz-txt-link-rfc2396E" href="mailto:Alex.Sierra@amd.com"><Alex.Sierra@amd.com></a>; <a class="moz-txt-link-abbreviated" href="mailto:amd-gfx@lists.freedesktop.org">amd-gfx@lists.freedesktop.org</a><br> <b>Subject:</b> Re: [PATCH] drm/amdkfd: drop process ref count when xnack disable<o:p></o:p></p> </div> </div> <p class="MsoNormal"><o:p> </o:p></p> <p class="MsoNormal">[CAUTION: External Email] <o:p></o:p></p> <div> <p><o:p> </o:p></p> <div> <p class="MsoNormal">On 2021-08-31 10:41 p.m., Alex Sierra wrote:<o:p></o:p></p> </div> <blockquote style="margin-top:5.0pt;margin-bottom:5.0pt"> <pre>During svm restore pages interrupt handler, kfd_process ref count was<o:p></o:p></pre> <pre>never dropped when xnack was disabled. Therefore, the object was never<o:p></o:p></pre> <pre>released.<o:p></o:p></pre> </blockquote> <p>Good catch, but if xnack is off, we should not get here to recover fault.<o:p></o:p></p> <p>The fix looks good to me.<o:p></o:p></p> <p>Reviewed-by: Philip Yang <a href="mailto:philip.yang@amd.com" moz-do-not-send="true"><philip.yang@amd.com></a><o:p></o:p></p> <blockquote style="margin-top:5.0pt;margin-bottom:5.0pt"> <pre><o:p> </o:p></pre> <pre>Signed-off-by: Alex Sierra <a href="mailto:alex.sierra@amd.com" moz-do-not-send="true"><alex.sierra@amd.com></a><o:p></o:p></pre> <pre>---<o:p></o:p></pre> <pre> drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 3 ++-<o:p></o:p></pre> <pre> 1 file changed, 2 insertions(+), 1 deletion(-)<o:p></o:p></pre> <pre><o:p> </o:p></pre> <pre>diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c<o:p></o:p></pre> <pre>index 8f9b5b53dab5..110c46cd7fac 100644<o:p></o:p></pre> <pre>--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c<o:p></o:p></pre> <pre>+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c<o:p></o:p></pre> <pre>@@ -2484,7 +2484,8 @@ svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,<o:p></o:p></pre> <pre> }<o:p></o:p></pre> <pre> if (!p->xnack_enabled) {<o:p></o:p></pre> <pre> pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);<o:p></o:p></pre> <pre>- return -EFAULT;<o:p></o:p></pre> <pre>+ r = -EFAULT;<o:p></o:p></pre> <pre>+ goto out;<o:p></o:p></pre> <pre> }<o:p></o:p></pre> <pre> svms = &p->svms;<o:p></o:p></pre> <pre> <o:p></o:p></pre> </blockquote> </div> </div> </div> </div> </blockquote> </body> </html>