I'm using the iMX6 SoloX SABRE board with Framebuffer backend (no X11) and encountered an issue during developing an EGL application.
The following, rather simple, test-application crashes (see attached eglinitialize-bug.c for full source) with a kernel panic (see attached kernel-panic.txt).
int main(int argc, char **argv)
mlockall(MCL_CURRENT | MCL_FUTURE);
native_display = fbGetDisplayByIndex(0);
native_window = fbCreateWindow(native_display, 0, 0, 0, 0);
// The following call produces kernel panic if mlockall(MCL_FUTURE) has been called
Excerpt of the kernel panic:
[<800b8054>] (remap_pfn_range) from [<80018928>] (arm_dma_mmap+0xc8/0xcc)
[<80018928>] (arm_dma_mmap) from [<804b3938>] (gckOS_MapMemory+0x18c/0x224)
[<804b3938>] (gckOS_MapMemory) from [<804b93b8>] (drv_open+0xb4/0x158)
[<804b93b8>] (drv_open) from [<800d8a5c>] (chrdev_open+0xa4/0x178)
If I remove the call of mlockall in the application, the kernel panic does not happen. Unfortunately, in my real use-case, the function mlockall is called by a close-sourced framework we are using, i.e. I cannot modify that. According to the stack trace, the Vivante driver seems to be the culprit, or is at least involved.
Is this intended or a known bug? Why does the Vivante GPU-driver crash or cause a crash in this situation?
I'm using 3.14.28 and also have tried with 3.14.38.
I'm cross-compiling (with Yocto toolchain) the .c file with:
$(CC) -o eglinitialize-bug eglinitialize-bug.c -DLINUX -DEGL_API_FB -lc -lEGL
Original Attachment has been moved to: eglinitialize-bug.c.zip
Original Attachment has been moved to: kernel-panic.txt.zip