The emulation for single and double precision multiply accumulate
instructions correctly normalised any denormal values in the operand
registers, but failed to normalise the destination (accumulator)
register.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=70501

Signed-off-by: Jay Foad <[email protected]>
---
 arch/arm/vfp/vfpdouble.c | 2 ++
 arch/arm/vfp/vfpsingle.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/arch/arm/vfp/vfpdouble.c b/arch/arm/vfp/vfpdouble.c
index 6cac43bd1d86..423f56dd4028 100644
--- a/arch/arm/vfp/vfpdouble.c
+++ b/arch/arm/vfp/vfpdouble.c
@@ -866,6 +866,8 @@ vfp_double_multiply_accumulate(int dd, int dn, int dm, u32 
fpscr, u32 negate, ch
                vdp.sign = vfp_sign_negate(vdp.sign);
 
        vfp_double_unpack(&vdn, vfp_get_double(dd));
+       if (vdn.exponent == 0 && vdn.significand)
+               vfp_double_normalise_denormal(&vdn);
        if (negate & NEG_SUBTRACT)
                vdn.sign = vfp_sign_negate(vdn.sign);
 
diff --git a/arch/arm/vfp/vfpsingle.c b/arch/arm/vfp/vfpsingle.c
index b252631b406b..4f96c1617aae 100644
--- a/arch/arm/vfp/vfpsingle.c
+++ b/arch/arm/vfp/vfpsingle.c
@@ -915,6 +915,8 @@ vfp_single_multiply_accumulate(int sd, int sn, s32 m, u32 
fpscr, u32 negate, cha
        v = vfp_get_float(sd);
        pr_debug("VFP: s%u = %08x\n", sd, v);
        vfp_single_unpack(&vsn, v);
+       if (vsn.exponent == 0 && vsn.significand)
+               vfp_single_normalise_denormal(&vsn);
        if (negate & NEG_SUBTRACT)
                vsn.sign = vfp_sign_negate(vsn.sign);
 
-- 
1.8.3.2

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