909663 - Canvas cause system freezing in several cases

Status: RESOLVED DUPLICATE of bug 903969

(Firefox OS Graveyard :: Gaia, defect)

Description

[Greg Weng [:snowmantw][:gweng][:λ]]

STR(1):

1. Create a custom application with a canvas element. In my case, I insert a canvas element in a customized keyboard to test the hand writing
2. Bind the element with 'mousemove' event to draw the whole track according to the points trigger by the event
3. Draw as fast as the hand writing speed

Expected:
Canvas drawing without any problem, like what it does on the browser on desktop.

Actual Result:
1. System freeze when user draw it too fast
2. adb logcat throw lots duplicated errors like crazy:

> E/libgenlock(  530): perform_lock_unlock_operation: GENLOCK_IOC_LOCK failed (lockType0x0, err=Invalid argument fd=190)

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STR(2):

1. Long press on any icon on homescreen
2. Move it left or right

Expected:
Icon moves and can be placed at a new place

Actual Result:
1. System freeze
2. adb logcat throw lots duplicated errors as STR(1)

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At first I thought it was caused by my app which may use the incorrect way to manipulate the canvas element, but I began to feel that I should report this after I tried the second case in which I heard it was also represented by canvas, and it throw the same error as well.

I've also read the RESOLVED FIXED Bug 896286. Although it seems irrelated with these two cases because it's about the Marketplace, the situation and the error messages is just the same. 

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Tested on Unagi/B2G 26.01a1-2013082204022/Gaia 1.2.0 master branch