Bug 72455 – QNX StackBase doesn't take guard page into account

• Status: RESOLVED
• Resolution: FIXED
• Component: Platform

[George Staikos]

Created attachment 115305 [details]
Patch to fix the crash by excluding the guard page from the stack.

There is a 4kb guard page on the stack on QNX.  The current code doesn't take this into account, causing it to crash before hitting the recursion/stack guard in WTF.  Crashes multiple layout tests including large-expressions.js and regress-96526-002.js

[George Staikos]

Comment on attachment 115305 [details]
Patch to fix the crash by excluding the guard page from the stack.

Missing changelog

[George Staikos]

Created attachment 115314 [details]
Add patch with changelog

[Daniel Bates]

Comment on attachment 115314 [details]
Add patch with changelog

View in context: https://bugs.webkit.org/attachment.cgi?id=115314&action=review

Thanks for the patch!

> Source/JavaScriptCore/wtf/StackBounds.cpp:110
> +    m_bound = static_cast<char*>(stackBase) + 0x1000; // 4kb guard page

This is OK as-is. We should look to query the OS for the page size.

[WebKit Review Bot]

Comment on attachment 115314 [details]
Add patch with changelog

Clearing flags on attachment: 115314

Committed r100406: <http://trac.webkit.org/changeset/100406>

[WebKit Review Bot]

All reviewed patches have been landed.  Closing bug.

[George Staikos]

(In reply to comment #3)
> (From update of attachment 115314 [details])
> View in context: https://bugs.webkit.org/attachment.cgi?id=115314&action=review
> 
> Thanks for the patch!
> 
> > Source/JavaScriptCore/wtf/StackBounds.cpp:110
> > +    m_bound = static_cast<char*>(stackBase) + 0x1000; // 4kb guard page
> 
> This is OK as-is. We should look to query the OS for the page size.

There is no way to do that yet other than read the book, as far as I know.