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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: D5CC8180008 X-Stat-Signature: 665zwz3qemjtc8jpb3xordqj61147e3m X-Rspam-User: X-HE-Tag: 1671813538-915114 X-HE-Meta: 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 /xXbZ7sb caI/u65PIRA4irCZYAO915/x4T9BMM5X6AcBVQ93wfkd5MDbKp09np9Vc3jaxrw1zTG0Hq+QMFPyBr3xw3GFSVwaGetQz8r18a+1/fJ6+DDeF60npXdfW1jRa5PN6l5k+3Rkc X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > @@ -280,14 +268,14 @@ void dma_pool_destroy(struct dma_pool *pool) > mutex_unlock(&pools_reg_lock); > > list_for_each_entry_safe(page, tmp, &pool->page_list, page_list) { > + if (!is_page_busy(page)) > + dma_free_coherent(pool->dev, pool->allocation, > + page->vaddr, page->dma); > + else > dev_err(pool->dev, "%s %s, %p busy\n", __func__, > pool->name, page->vaddr); > + list_del(&page->page_list); > + kfree(page); Hmm. The is_page_busy case is really a should not happen case. What is the benefit of skipping the dma_free_coherent and leaking memory here, vs letting KASAN and friends see the free and possibly help with debugging? In other words, why is this not: WARN_ON_ONCE(is_page_busy(page)); dma_free_coherent(pool->dev, pool->allocation, page->vaddr, page->dma); ... > page->in_use--; > *(int *)vaddr = page->offset; > page->offset = offset; > - /* > - * Resist a temptation to do > - * if (!is_page_busy(page)) pool_free_page(pool, page); > - * Better have a few empty pages hang around. > - */ This doesn't look related to the rest, or am I missing something?