Hi, I was able find the root cause of this bug and will send a fix soon! > Unable to handle kernel paging request at virtual address ffff0000c2a80e68 We are running this test on Qemu with '-cpu max', this means 52-bit virtual addresses are being used. The trampolines generation code has the following two lines: emit_addr_mov_i64(A64_R(0), (const u64)im, ctx); emit_call((const u64)__bpf_tramp_enter, ctx); here the address of struct bpf_tramp_image is moved to R0 and passed as an argument to __bpf_tramp_enter(). emit_addr_mov_i64() assumes that the address passed to it is in the vmalloc space and uses at most 48 bits. It sets all the remaining bits to 1. but struct bpf_tramp_image is allocated using kzalloc() and when 52-bit VAs are used, its address is not guaranteed to be 48-bit, therefore we see this bug, where 0xfff[0]0000c2a80e68 is converted to 0xfff[f]0000c2a80e68 when the trampoline is generated. The fix would be use emit_a64_mov_i64() for moving this address into R0. Thanks, Puranjay
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