<html><head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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Hi Kevin,<br>
<br>
yes and that is perfectly valid and expected behavior. There is
absolutely no need to change anything in TTM here.<br>
<br>
What we could do is:<br>
1) Change the test case to use something larger than 1TiB.<br>
2) Change kvmalloc to allow GFP_ZERO allocations even in the vmalloc
fallback path.<br>
<br>
Regards,<br>
Christian.<br>
<br>
<div class="moz-cite-prefix">Am 20.04.22 um 14:39 schrieb Wang,
Yang(Kevin):<br>
</div>
<blockquote type="cite" cite="mid:CO6PR12MB54735D4B8E05AB1C17D356AE82F59@CO6PR12MB5473.namprd12.prod.outlook.com">
<style type="text/css" style="display:none;">P {margin-top:0;margin-bottom:0;}</style>
<p style="font-family:Arial;font-size:10pt;color:#0000FF;margin:5pt;" align="Left">
[AMD Official Use Only]<br>
</p>
<br>
<div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">Hi Chirs,</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">yes, right, the amdgpu
drive rwill use </span><span style="font-family: Calibri,
Arial, Helvetica, sans-serif; font-size: 12pt;
background-color: rgba(0, 0, 0, 0); color: rgb(0, 0, 0);
display: inline !important;">amdgpu_bo_validate_size()
function to verify bo size,</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; background-color: rgba(0, 0, 0,
0); display: inline !important; color: rgb(0, 0, 0);">but
when driver try to allocate VRAM domain bo fail, the amdgpu
driver will fall back to allocate domain = (GTT | VRAM) bo.</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-size: 12pt; font-family: Calibri, Arial,
Helvetica, sans-serif; background-color: rgba(0, 0, 0, 0);
display: inline !important; color: rgb(0, 0, 0);">please
check following code, it will cause the 2</span><span style="font-family: Calibri, Arial, Helvetica, sans-serif;
background-color: rgba(0, 0, 0, 0); color: rgb(0, 0, 0);
display: inline !important;"><span style="font-size:
13.3333px;">nd time</span><span style="font-size: 12pt;"> to
allocate bo fail during allocate 256Mb buffer to store dma
address (via kvmalloc()).</span></span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-family:"Segoe UI", "Segoe UI
Web (West European)", "Segoe UI",
-apple-system, BlinkMacSystemFont, Roboto, "Helvetica
Neue",
sans-serif;font-size:14px;background-color:rgb(255, 255,
255);display:inline !important"><br>
</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; background-color: rgba(0, 0, 0,
0); display: inline !important; color: rgb(0, 0, 0);">
initial_domain = (u32)(0xffffffff &
args->in.domains);</span><span style="font-family:"Segoe UI", "Segoe UI Web
(West European)", "Segoe UI", -apple-system,
BlinkMacSystemFont, Roboto, "Helvetica Neue",
sans-serif;font-size:14px;background-color:rgb(255, 255,
255);display:inline !important">
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">retry:</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);"> r =
amdgpu_gem_object_create(adev, size,
args->in.alignment,</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">
initial_domain,</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">
flags, ttm_bo_type_device, resv,
&gobj);</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);"> if (r
&& r != -ERESTARTSYS) {</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);"> if
(flags & AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED) {</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">
flags &= ~AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED;</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">
goto retry;</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);"> }</span></div>
<div><br>
</div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);"> if
(initial_domain == AMDGPU_GEM_DOMAIN_VRAM) {</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">
initial_domain |= AMDGPU_GEM_DOMAIN_GTT;</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">
goto retry;</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);"> }</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">
DRM_DEBUG("Failed to allocate GEM object (%llu, %d,
%llu, %d)\n",</span></div>
<div><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">
size, initial_domain, args->in.alignment,
r);</span></div>
</span><span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; background-color: rgba(0, 0, 0,
0); display: inline !important; color: rgb(0, 0, 0);">
}</span><span style="font-family:"Segoe UI",
"Segoe UI Web (West European)", "Segoe
UI", -apple-system, BlinkMacSystemFont, Roboto,
"Helvetica Neue",
sans-serif;font-size:14px;background-color:rgb(255, 255,
255);display:inline !important"><br>
</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<br>
</div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">Best Regards,</span></div>
<div style="font-family: Calibri, Arial, Helvetica, sans-serif;
font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-family: Calibri, Arial, Helvetica,
sans-serif; font-size: 12pt; color: rgb(0, 0, 0);
background-color: rgba(0, 0, 0, 0);">Kevin</span></div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<hr tabindex="-1" style="display:inline-block; width:98%">
<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b>
Christian König <a class="moz-txt-link-rfc2396E" href="mailto:ckoenig.leichtzumerken@gmail.com"><ckoenig.leichtzumerken@gmail.com></a><br>
<b>Sent:</b> Wednesday, April 20, 2022 7:55 PM<br>
<b>To:</b> Wang, Yang(Kevin) <a class="moz-txt-link-rfc2396E" href="mailto:KevinYang.Wang@amd.com"><KevinYang.Wang@amd.com></a>;
Koenig, Christian <a class="moz-txt-link-rfc2396E" href="mailto:Christian.Koenig@amd.com"><Christian.Koenig@amd.com></a>;
<a class="moz-txt-link-abbreviated" href="mailto:dri-devel@lists.freedesktop.org">dri-devel@lists.freedesktop.org</a>
<a class="moz-txt-link-rfc2396E" href="mailto:dri-devel@lists.freedesktop.org"><dri-devel@lists.freedesktop.org></a>;
<a class="moz-txt-link-abbreviated" href="mailto:amd-gfx@lists.freedesktop.org">amd-gfx@lists.freedesktop.org</a>
<a class="moz-txt-link-rfc2396E" href="mailto:amd-gfx@lists.freedesktop.org"><amd-gfx@lists.freedesktop.org></a><br>
<b>Subject:</b> Re: [PATCH] drm/ttm: fix ttm tt init fail
when size exceeds kmalloc limit</font>
<div> </div>
</div>
<div class="elementToProof">Hi Kevin,<br>
<br>
no, the test case should already fail in
amdgpu_bo_validate_size().<br>
<br>
If we have a system with 2TiB of memory where the test case
could succeed then we should increase the requested size to
something larger.<br>
<br>
And if the underlying core Linux kernel functions don't allow
allocations as large as the requested one we should *NEVER*
ever add workarounds like this.<br>
<br>
It is perfectly expected that this test case is not able to
fulfill the desired allocation. That it fails during kvmalloc
is unfortunate, but not a show stopper.<br>
<br>
Regards,<br>
Christian.<br>
<br>
<br>
<div class="x_moz-cite-prefix">Am 20.04.22 um 13:32 schrieb
Wang, Yang(Kevin):<br>
</div>
<blockquote type="cite">
<p style="margin-top: 0px; margin-bottom:
0px;font-family:Arial; font-size:10pt; color:#0000FF;
margin:5pt" align="Left">
[AMD Official Use Only]<br>
</p>
<br>
<div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0);
background-color:rgba(0,0,0,0)">Hi Chris,</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0);
background-color:rgba(0,0,0,0)">you misunderstood
background about this case.</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0);
background-color:rgba(0,0,0,0)"><br>
</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0);
background-color:rgba(0,0,0,0)">a</span><span style="color:rgb(0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; background-color:rgba(0,0,0,0)">lthough
we expect this test case to fail, it should fail at
the location where the Bo actual memory is actually
allocated. now the code logic will cause the failure
to allocate memory to store DMA address.</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; background-color:rgba(0,0,0,0)"><br>
</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; background-color:rgba(0,0,0,0)"><span style="background-color:rgb(255,255,255);
display:inline!important">e.g: </span>the case is
failed in 2TB system ram machine, it should be
allocated successful, but it is failed.</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt"><br>
</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; background-color:rgba(0,0,0,0)">allocate
1TB BO, the ttm should allocate 1TB/4k * 8 buffer to
store allocate result (page address), this should not
be failed usually.</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0); font-size:12pt;
background-color:rgba(0,0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif"><br>
</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0); font-size:12pt;
background-color:rgba(0,0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif">There
is a similar fix in upstream kernel 5.18, b</span><span style="color:rgb(0,0,0); font-size:12pt;
background-color:rgba(0,0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif">efore
this fix entered the TTM code, this problem existed in
TTM.</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0); font-size:12pt;
background-color:rgba(0,0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif"><br>
</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="color:rgb(0,0,0); font-size:12pt;
background-color:rgba(0,0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif"><a href="https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgit.kernel.org%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Ftorvalds%2Flinux.git%2Fcommit%2F%3Fh%3Dv5.18-rc3%26id%3Da421ef303008b0ceee2cfc625c3246fa7654b0ca&data=05%7C01%7CKevinYang.Wang%40amd.com%7C2e9fd86a27d64a39432508da22c4b1f1%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637860525454702938%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=CiP9x3grwQ2aXFZPjpsAtwLCpBVeJufbGngy%2BtXLFbM%3D&reserved=0" data-auth="Verified" originalsrc="https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v5.18-rc3&id=a421ef303008b0ceee2cfc625c3246fa7654b0ca" shash="KMFRekIa5um9dneRj4pqsGBn2wIcYBwLUel6we5AalD06U/g9WcKPxBwS4F9Mgfpnqpq0GbN+8AA16pzy6v+Ay23e5shnO53IP8e7UcwQUE0fw1Wd4T+gBBF8PJiMugXDZiWlVYrV3tySgoFbmz+CuFzrYJbobUVj6E5khawPfo=" id="LPlnk660272" moz-do-not-send="true">kernel/git/torvalds/linux.git
- Linux kernel source tree</a><br>
</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span class="x_commit-subject" style="font-size:12pt;
margin:1.5em 0em 0.5em; padding:0em; color:rgb(0,0,0);
font-family:Calibri,Arial,Helvetica,sans-serif;
background-color:rgb(255,255,255)">mm: allow
!GFP_KERNEL allocations for kvmalloc</span><br>
</div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<div><br>
</div>
<span style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0);
background-color:rgba(0,0,0,0)">Best Regards,</span></div>
<div class="x_elementToProof" style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<span style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0);
background-color:rgba(0,0,0,0)">Kevin</span><br>
<div><br>
</div>
</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> Koenig, Christian
<a href="mailto:Christian.Koenig@amd.com" data-auth="NotApplicable" class="x_moz-txt-link-rfc2396E" moz-do-not-send="true">
<Christian.Koenig@amd.com></a><br>
<b>Sent:</b> Wednesday, April 20, 2022 6:53 PM<br>
<b>To:</b> Wang, Yang(Kevin) <a href="mailto:KevinYang.Wang@amd.com" data-auth="NotApplicable" class="x_moz-txt-link-rfc2396E" moz-do-not-send="true">
<KevinYang.Wang@amd.com></a>; <a href="mailto:dri-devel@lists.freedesktop.org" data-auth="NotApplicable" class="x_moz-txt-link-abbreviated
moz-txt-link-freetext" moz-do-not-send="true">
dri-devel@lists.freedesktop.org</a> <a href="mailto:dri-devel@lists.freedesktop.org" data-auth="NotApplicable" class="x_moz-txt-link-rfc2396E" moz-do-not-send="true">
<dri-devel@lists.freedesktop.org></a>; <a href="mailto:amd-gfx@lists.freedesktop.org" data-auth="NotApplicable" class="x_moz-txt-link-abbreviated
moz-txt-link-freetext" moz-do-not-send="true">
amd-gfx@lists.freedesktop.org</a> <a href="mailto:amd-gfx@lists.freedesktop.org" data-auth="NotApplicable" class="x_moz-txt-link-rfc2396E" moz-do-not-send="true">
<amd-gfx@lists.freedesktop.org></a><br>
<b>Subject:</b> Re: [PATCH] drm/ttm: fix ttm tt init
fail when size exceeds kmalloc limit</font>
<div> </div>
</div>
<div>Am 20.04.22 um 11:07 schrieb Wang, Yang(Kevin):<br>
<blockquote type="cite">
<p style="margin-top: 0px; margin-bottom:
0px;margin-top:0px; margin-bottom:0px;
font-family:Arial; font-size:10pt; color:#0000FF;
margin:5pt" align="Left">
[AMD Official Use Only]<br>
</p>
<br>
<div>
<div style="font-family:Calibri,Arial,Helvetica,sans-serif;
font-size:12pt; color:rgb(0,0,0)">
<br>
</div>
<hr tabindex="-1" style="display:inline-block;
width:98%">
<div id="x_x_divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri,
sans-serif" color="#000000"><b>From:</b> Koenig,
Christian
<a href="mailto:Christian.Koenig@amd.com" data-auth="NotApplicable" class="x_x_moz-txt-link-rfc2396E" moz-do-not-send="true">
<Christian.Koenig@amd.com></a><br>
<b>Sent:</b> Wednesday, April 20, 2022 5:00 PM<br>
<b>To:</b> Wang, Yang(Kevin) <a href="mailto:KevinYang.Wang@amd.com" data-auth="NotApplicable" class="x_x_moz-txt-link-rfc2396E" moz-do-not-send="true">
<KevinYang.Wang@amd.com></a>; <a href="mailto:dri-devel@lists.freedesktop.org" data-auth="NotApplicable" class="x_x_moz-txt-link-abbreviated
x_moz-txt-link-freetext moz-txt-link-freetext" moz-do-not-send="true">
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<dri-devel@lists.freedesktop.org></a>; <a href="mailto:amd-gfx@lists.freedesktop.org" data-auth="NotApplicable" class="x_x_moz-txt-link-abbreviated
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<amd-gfx@lists.freedesktop.org></a><br>
<b>Subject:</b> Re: [PATCH] drm/ttm: fix ttm tt
init fail when size exceeds kmalloc limit</font>
<div> </div>
</div>
<div class="x_x_BodyFragment"><font size="2"><span style="font-size:11pt">
<div class="x_x_PlainText x_x_elementToProof">Am
20.04.22 um 10:56 schrieb Yang Wang:<br>
> if the __GFP_ZERO is set, the
kvmalloc() can't fallback to use vmalloc()<br>
<br>
Hui what? Why should kvmalloc() not be able
to fallback to vmalloc() <br>
when __GFP_ZERO is set?<br>
<br>
And even that is really the case then that
sounds like a bug in kvmalloc().</div>
<div class="x_x_PlainText x_x_elementToProof"><br>
Regards,<br>
Christian.</div>
<div class="x_x_PlainText x_x_elementToProof"><br>
<div class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">
[kevin]:</div>
</div>
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">it is
really test case from libdrm amdgpu test,
which try to allocate a big BO which will
cause ttm tt init fail.</span><br>
</div>
</span></font></div>
</div>
</blockquote>
<br>
<br>
LOL! Guys, this test case is intended to fail!<br>
<b><br>
</b>The test consists of allocating a buffer so
ridiculous large that it should never succeed and be
rejected by the kernel driver.<br>
<br>
This patch here is a really clear NAK.<br>
<br>
Regards,<br>
Christian.<br>
<br>
<blockquote type="cite">
<div>
<div class="x_x_BodyFragment"><font size="2"><span style="font-size:11pt">
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">it may
be a kvmalloc() bug, and this patch can as
a workaround in<span style="background-color:rgb(255,255,255);
display:inline!important"> ttm</span> before
this issue fix.</span></div>
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)"><br>
</span></div>
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">void
*kvmalloc_node(size_t size, gfp_t flags,
int node) <br>
</span></div>
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">{</span></div>
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">...</span></div>
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">
if ((flags & GFP_KERNEL) !=
GFP_KERNEL)<br>
</span></div>
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">
return kmalloc_node(size, flags,
node);<br>
</span></div>
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">...</span></div>
<div class="x_x_PlainText x_x_elementToProof"><span class="x_x_PlainText" style="margin:0px;
background-color:rgb(255,255,255)">}</span></div>
<div class="x_x_PlainText x_x_elementToProof"><br>
</div>
<div class="x_x_PlainText x_x_elementToProof">Best
Regards,</div>
<div class="x_x_PlainText x_x_elementToProof">Kevin<br>
<br>
> to allocate memory, when request size
is exceeds kmalloc limit, it will<br>
> cause allocate memory fail.<br>
><br>
> e.g: when ttm want to create a BO with
1TB size, it maybe fail.<br>
><br>
> Signed-off-by: Yang Wang <a href="mailto:KevinYang.Wang@amd.com" data-auth="NotApplicable" class="x_x_moz-txt-link-rfc2396E" moz-do-not-send="true">
<KevinYang.Wang@amd.com></a><br>
> ---<br>
> drivers/gpu/drm/ttm/ttm_tt.c | 14
+++++++++++---<br>
> 1 file changed, 11 insertions(+), 3
deletions(-)<br>
><br>
> diff --git
a/drivers/gpu/drm/ttm/ttm_tt.c
b/drivers/gpu/drm/ttm/ttm_tt.c<br>
> index 79c870a3bef8..9f2f3e576b8d 100644<br>
> --- a/drivers/gpu/drm/ttm/ttm_tt.c<br>
> +++ b/drivers/gpu/drm/ttm/ttm_tt.c<br>
> @@ -97,9 +97,12 @@ int
ttm_tt_create(struct ttm_buffer_object *bo,
bool zero_alloc)<br>
> static int
ttm_tt_alloc_page_directory(struct ttm_tt
*ttm)<br>
> {<br>
> ttm->pages =
kvmalloc_array(ttm->num_pages,
sizeof(void*),<br>
> - GFP_KERNEL |
__GFP_ZERO);<br>
> +
GFP_KERNEL);<br>
> if (!ttm->pages)<br>
> return -ENOMEM;<br>
> +<br>
> + memset(ttm->pages, 0,
ttm->num_pages * sizeof(void *));<br>
> +<br>
> return 0;<br>
> }<br>
> <br>
> @@ -108,10 +111,12 @@ static int
ttm_dma_tt_alloc_page_directory(struct
ttm_tt *ttm)<br>
> ttm->pages =
kvmalloc_array(ttm->num_pages,<br>
>
sizeof(*ttm->pages) +<br>
>
sizeof(*ttm->dma_address),<br>
> -
GFP_KERNEL | __GFP_ZERO);<br>
> +
GFP_KERNEL);<br>
> if (!ttm->pages)<br>
> return -ENOMEM;<br>
> <br>
> + memset(ttm->pages, 0,
ttm->num_pages * (sizeof(*ttm->pages)
+ sizeof(*ttm->dma_address)));<br>
> +<br>
> ttm->dma_address = (void
*)(ttm->pages + ttm->num_pages);<br>
> return 0;<br>
> }<br>
> @@ -120,9 +125,12 @@ static int
ttm_sg_tt_alloc_page_directory(struct ttm_tt
*ttm)<br>
> {<br>
> ttm->dma_address =
kvmalloc_array(ttm->num_pages,<br>
>
sizeof(*ttm->dma_address),<br>
> -
GFP_KERNEL | __GFP_ZERO);<br>
> +
GFP_KERNEL);<br>
> if (!ttm->dma_address)<br>
> return -ENOMEM;<br>
> +<br>
> + memset(ttm->dma_address, 0,
ttm->num_pages *
sizeof(*ttm->dma_address));<br>
> +<br>
> return 0;<br>
> }<br>
> <br>
<br>
</div>
</span></font></div>
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