Hello , All I think I'm on wright way: I change /arch/mips/mm/tlbex.c: --- /home/artpol/router/buildroot/kernels/linux-2.6.16-old/arch/mips/mm/tlbex.c 2006-03-20 11:35:39.000000000 +0000 +++ tlbex.c 2006-05-31 16:57:58.000000000 +0000 @@ -742,7 +742,7 @@ } #endif - memcpy((void *)CAC_BASE, tlb_handler, 0x80); + memcpy((void *)ebase, tlb_handler, 0x80); } /* @@ -838,6 +838,7 @@ break; case CPU_R4300: + case CPU_4KC: case CPU_5KC: case CPU_TX49XX: case CPU_AU1000: @@ -852,13 +853,12 @@ case CPU_R10000: case CPU_R12000: - case CPU_4KC: case CPU_SB1: case CPU_SB1A: case CPU_4KSC: case CPU_20KC: case CPU_25KF: - tlbw(p); + tlbw(p); break; case CPU_NEVADA: @@ -1260,7 +1260,7 @@ } #endif - memcpy((void *)CAC_BASE, final_handler, 0x100); + memcpy((void *)ebase, final_handler, 0x100); } And it seem than no problem now (`cat /bin/busybox > box` work as much as need!). I think this is wright way, but not all - I'am not guru in memory subsystem and can miss something! So wait for your advices! -- Best regards, art mailto:art@xxxxxxxxxx