glReadPixels crash on iOS

Can not reproduce their own, online users can always appear,

No start to check this problem, please help, thank you

Various parameters of this method have been tested, can not reproduce the same problem. Our APP also has a gift module, also used openGL es, the feeling is too much GPU will be out of this problem, I wrote a special test program using a little GPU did not report the same error, this problem has troubled me more Month, do not know where to start to solve this problem.

libsystem_platform.dylib      0x0000000183223b40 _sigtramp + 36 (sigtramp.c:109)
AGXMetalA10                    0x00000001a2ce15d8 AGX::Texture<(AGXTextureMemoryLayout)1, AGX::G9::Encoders, AGX::G9::Classes>::readRegion(unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, void*, unsigned long, unsigned long) + 904 (agxa_texture_template.hpp:1038)
AGXMetalA10                    0x00000001a2ce15d8 AGX::Texture<(AGXTextureMemoryLayout)1, AGX::G9::Encoders, AGX::G9::Classes>::readRegion(unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, unsigned int, void*, unsigned long, unsigned long) + 904 (agxa_texture_template.hpp:1038)
AGXMetalA10                    0x00000001a2ccaa7c -[AGXA10FamilyTexture getBytes:bytesPerRow:bytesPerImage:fromRegion:mipmapLevel:slice:] + 84 (agxa_texture_objc.mm:355)
AppleMetalGLRenderer          0x00000001a2d3e8a0 gldReadFramebufferData + 1260 (glr_framebuffer.mm:549)
GLEngine                      0x00000001a3a98074 glReadPixels_Exec + 1124 (gl_read_pixels.c:329)
YXLiveMediaClientFW            0x0000000107aea874 -[YXPixelFormatGLConverter Render:outputBuffer:] + 344
YXLiveMediaClientFW            0x0000000107b23a64 -[YXGLView onRenderView:] + 1116
YXLiveMediaClientFW            0x0000000107b23ea0 -[YXGLView renderThread] + 352
Foundation                    0x0000000183fff0f4 __NSThread__start__ + 996 (NSThread.m:1181)
libsystem_pthread.dylib        0x00000001832282b4 _pthread_body + 308 (pthread.c:740)
libsystem_pthread.dylib        0x0000000183228180 _pthread_start + 312 (pthread.c:799)
libsystem_pthread.dylib        0x0000000183226b74 thread_start + 4

glReadPixels(0, 0, _mFBOSizeWidth, _mFBOSizeHeight, GL_RGBA, GL_UNSIGNED_BYTE, outputBuffer);