On Thu, 14 Sep 2023 13:17:00 -0400
Steven Rostedt [off-list ref] wrote:

Now lets look at big endian layout:

 uaddr = 0xbeef0004
 enabler = 1;

 memory at 0xbeef0000:  00 00 00 00 00 00 00 02
                                    ^
                                    addr: 0xbeef0004

				(enabler is set )

	bitoffset = uaddr & (sizeof(unsigned long) - 1); bitoffset = 4
	bit_offset *= 8;				 bitoffset = 32
	uaddr &= ~(sizeof(unsigned long) - 1);		 uaddr = 0xbeef0000

	ptr = kaddr + (uaddr & ~PAGE_MASK);

	clear_bit(1 + 32, ptr);

 memory at 0xbeef0000:  00 00 00 00 00 00 00 02
                                  ^
				bit 33 of 0xbeef0000

I don't think that's what you expected!

I believe the above can be fixed with:

	bit_offset = uaddr & (sizeof(unsigned long) - 1);
	if (bit_offset) {
#ifdef CONFIG_CPU_BIG_ENDIAN
		bit_offest = 0;
#else
		bit_offset *= BITS_PER_BYTE;
#endif
		uaddr &= ~(sizeof(unsigned long) - 1);
	}

-- Steve