Bug 221198 - CeilingOnPageSize too low for Loongson CPUs
Summary: CeilingOnPageSize too low for Loongson CPUs
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords: InRadar
: 223721 (view as bug list)
Depends on:
Blocks:
 
Reported: 2021-02-01 02:26 PST by Alberto Garcia
Modified: 2022-02-15 07:47 PST (History)
10 users (show)

See Also:


Attachments
Patch (1.48 KB, patch)
2021-05-15 15:57 PDT, Alberto Garcia
no flags Details | Formatted Diff | Diff

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Description Alberto Garcia 2021-02-01 02:26:46 PST
CeilingOnPageSize is set to 4KB for MIPS on Linux, but that value is not permitted on Loongson CPUs which have a 16KB page size:

https://sources.debian.org/src/linux/5.10.9-1/arch/mips/Kconfig/#L2213-L2215
Comment 1 Xan Lopez 2021-02-01 02:56:04 PST
Our guess is that we are crashing in WTF::pageSize():

        RELEASE_ASSERT_WITH_MESSAGE(s_pageSize <= CeilingOnPageSize, "CeilingOnPageSize is too low, raise it in PageBlock.h!");

For Loongson CPUs that will be 16 <= 4, which won't work.

We can change the general ceiling value for MIPS to something else, at least 16KB, or try to detect Loongson CPUs and change it just for those.
Comment 2 Alberto Garcia 2021-02-01 02:59:32 PST
(In reply to Xan Lopez from comment #1)
> We can change the general ceiling value for MIPS to something else,
> at least 16KB, or try to detect Loongson CPUs and change it just for
> those.

For distributions I don't think the latter is an option, because
there's no guarantee that the machine where the package is built is
the same where it is installed and run.

But I can patch that downstream if there's no good general solution.
Comment 3 Radar WebKit Bug Importer 2021-02-08 02:27:13 PST
<rdar://problem/74089683>
Comment 4 Alberto Garcia 2021-05-15 14:13:58 PDT
This was fixed for 32-bit MIPS in r276583 (bug 225030), I think we should also do it for MIPS64.
Comment 5 Michael Catanzaro 2021-05-15 15:46:19 PDT
(In reply to Alberto Garcia from comment #4)
> This was fixed for 32-bit MIPS in r276583 (bug 225030), I think we should
> also do it for MIPS64.

Do it!
Comment 6 Alberto Garcia 2021-05-15 15:57:25 PDT
Created attachment 428747 [details]
Patch
Comment 7 EWS 2021-05-15 16:55:01 PDT
Committed r277551 (237779@main): <https://commits.webkit.org/237779@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 428747 [details].
Comment 8 Michael Catanzaro 2022-02-15 07:47:51 PST
*** Bug 223721 has been marked as a duplicate of this bug. ***