Bedding, in these few lines, is less a comfort than a verdict. The speaker looks at "her winter linen" and finds "little to whistle about": nothing cheerful, nothing to lift the spirits. The "her" is left unexplained, and it could be a woman making the bed, or winter itself personified as a housekeeper. The poem doesn't say, and that ambiguity is part of its charm.
The second stanza turns the sheets into a "cold surgeon." Surgeons cut and clean, and here the cure is aimed at "unnecessary dust and ease." That's a surprising pairing. Dust is literal, but ease sounds like laziness or comfort, so the clean linen seems to strip away both mess and softness.
The speaker's feeling seems mixed. There's a shiver of disapproval, yet also a grudging respect for this sharp, bracing order. The mood is crisp, chilly, and austere, like climbing into a bed that is spotless but not yet warm.