 This phase I trial is studying the side effects and best dose of sorafenib in treating patients with metastatic or unresectable solid tumors, multiple myeloma, or non-Hodgkins lymphoma with or without impaired liver or kidney function. Sorafenib may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the cancer. Sorafenib may have different effects in patients who have changes in their liver or kidney function 