Commit e4ee3891 authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt Committed by Paul Mackerras
Browse files

[POWERPC] Alignment exception uses __get/put_user_inatomic 



Make the alignment exception handler use the new _inatomic variants
of __get/put_user. This fixes erroneous warnings in the very rare
cases where we manage to have copy_tofrom_user_inatomic() trigger
an alignment exception.

Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>

 arch/powerpc/kernel/align.c |   56 ++++++++++++++++++++++++--------------------
 1 file changed, 31 insertions(+), 25 deletions(-)
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent e68c825b

arch/powerpc/kernel/align.c

+31 −25
Original line number Diff line number Diff line
@@ -241,7 +241,7 @@ static int emulate_dcbz(struct pt_regs *regs, unsigned char __user *addr) 
	if (user_mode(regs) && !access_ok(VERIFY_WRITE, p, size))

		return -EFAULT;

	for (i = 0; i < size / sizeof(long); ++i)

		if (__put_user(0, p+i))

		if (__put_user_inatomic(0, p+i))

			return -EFAULT;

	return 1;

}
@@ -288,7 +288,8 @@ static int emulate_multiple(struct pt_regs *regs, unsigned char __user *addr, 
		} else {

			unsigned long pc = regs->nip ^ (swiz & 4);



			if (__get_user(instr, (unsigned int __user *)pc))

			if (__get_user_inatomic(instr,

						(unsigned int __user *)pc))

				return -EFAULT;

			if (swiz == 0 && (flags & SW))

				instr = cpu_to_le32(instr);
@@ -324,26 +325,30 @@ static int emulate_multiple(struct pt_regs *regs, unsigned char __user *addr, 
			       ((nb0 + 3) / 4) * sizeof(unsigned long));



		for (i = 0; i < nb; ++i, ++p)

			if (__get_user(REG_BYTE(rptr, i ^ bswiz), SWIZ_PTR(p)))

			if (__get_user_inatomic(REG_BYTE(rptr, i ^ bswiz),

						SWIZ_PTR(p)))

				return -EFAULT;

		if (nb0 > 0) {

			rptr = &regs->gpr[0];

			addr += nb;

			for (i = 0; i < nb0; ++i, ++p)

				if (__get_user(REG_BYTE(rptr, i ^ bswiz),

				if (__get_user_inatomic(REG_BYTE(rptr,

								 i ^ bswiz),

							SWIZ_PTR(p)))

					return -EFAULT;

		}



	} else {

		for (i = 0; i < nb; ++i, ++p)

			if (__put_user(REG_BYTE(rptr, i ^ bswiz), SWIZ_PTR(p)))

			if (__put_user_inatomic(REG_BYTE(rptr, i ^ bswiz),

						SWIZ_PTR(p)))

				return -EFAULT;

		if (nb0 > 0) {

			rptr = &regs->gpr[0];

			addr += nb;

			for (i = 0; i < nb0; ++i, ++p)

				if (__put_user(REG_BYTE(rptr, i ^ bswiz),

				if (__put_user_inatomic(REG_BYTE(rptr,

								 i ^ bswiz),

							SWIZ_PTR(p)))

					return -EFAULT;

		}
@@ -398,7 +403,8 @@ int fix_alignment(struct pt_regs *regs) 


		if (cpu_has_feature(CPU_FTR_PPC_LE) && (regs->msr & MSR_LE))

			pc ^= 4;

		if (unlikely(__get_user(instr, (unsigned int __user *)pc)))

		if (unlikely(__get_user_inatomic(instr,

						 (unsigned int __user *)pc)))

			return -EFAULT;

		if (cpu_has_feature(CPU_FTR_REAL_LE) && (regs->msr & MSR_LE))

			instr = cpu_to_le32(instr);
@@ -474,16 +480,16 @@ int fix_alignment(struct pt_regs *regs) 
		p = (unsigned long) addr;

		switch (nb) {

		case 8:

			ret |= __get_user(data.v[0], SWIZ_PTR(p++));

			ret |= __get_user(data.v[1], SWIZ_PTR(p++));

			ret |= __get_user(data.v[2], SWIZ_PTR(p++));

			ret |= __get_user(data.v[3], SWIZ_PTR(p++));

			ret |= __get_user_inatomic(data.v[0], SWIZ_PTR(p++));

			ret |= __get_user_inatomic(data.v[1], SWIZ_PTR(p++));

			ret |= __get_user_inatomic(data.v[2], SWIZ_PTR(p++));

			ret |= __get_user_inatomic(data.v[3], SWIZ_PTR(p++));

		case 4:

			ret |= __get_user(data.v[4], SWIZ_PTR(p++));

			ret |= __get_user(data.v[5], SWIZ_PTR(p++));

			ret |= __get_user_inatomic(data.v[4], SWIZ_PTR(p++));

			ret |= __get_user_inatomic(data.v[5], SWIZ_PTR(p++));

		case 2:

			ret |= __get_user(data.v[6], SWIZ_PTR(p++));

			ret |= __get_user(data.v[7], SWIZ_PTR(p++));

			ret |= __get_user_inatomic(data.v[6], SWIZ_PTR(p++));

			ret |= __get_user_inatomic(data.v[7], SWIZ_PTR(p++));

			if (unlikely(ret))

				return -EFAULT;

		}
@@ -551,16 +557,16 @@ int fix_alignment(struct pt_regs *regs) 
		p = (unsigned long) addr;

		switch (nb) {

		case 8:

			ret |= __put_user(data.v[0], SWIZ_PTR(p++));

			ret |= __put_user(data.v[1], SWIZ_PTR(p++));

			ret |= __put_user(data.v[2], SWIZ_PTR(p++));

			ret |= __put_user(data.v[3], SWIZ_PTR(p++));

			ret |= __put_user_inatomic(data.v[0], SWIZ_PTR(p++));

			ret |= __put_user_inatomic(data.v[1], SWIZ_PTR(p++));

			ret |= __put_user_inatomic(data.v[2], SWIZ_PTR(p++));

			ret |= __put_user_inatomic(data.v[3], SWIZ_PTR(p++));

		case 4:

			ret |= __put_user(data.v[4], SWIZ_PTR(p++));

			ret |= __put_user(data.v[5], SWIZ_PTR(p++));

			ret |= __put_user_inatomic(data.v[4], SWIZ_PTR(p++));

			ret |= __put_user_inatomic(data.v[5], SWIZ_PTR(p++));

		case 2:

			ret |= __put_user(data.v[6], SWIZ_PTR(p++));

			ret |= __put_user(data.v[7], SWIZ_PTR(p++));

			ret |= __put_user_inatomic(data.v[6], SWIZ_PTR(p++));

			ret |= __put_user_inatomic(data.v[7], SWIZ_PTR(p++));

		}

		if (unlikely(ret))

			return -EFAULT;

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