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Wed, 16 Dec 2020 07:47:35 +0000 Subject: Re: [patch 012/200] mm: slab: clarify krealloc()'s behavior with __GFP_ZERO To: Andy Shevchenko Cc: Andrew Morton , airlied@linux.ie, alexander.shishkin@linux.intel.com, bgolaszewski@baylibre.com, bp@alien8.de, bp@suse.de, cl@linux.com, daniel.vetter@ffwll.ch, daniel@ffwll.ch, gustavo@padovan.org, iamjoonsoo.kim@lge.com, james.morse@arm.com, jasowang@redhat.com, linus.walleij@linaro.org, linux-mm@kvack.org, maarten.lankhorst@linux.intel.com, mchehab@kernel.org, mm-commits@vger.kernel.org, mripard@kernel.org, mst@redhat.com, penberg@kernel.org, perex@perex.cz, rientjes@google.com, rric@kernel.org, sumit.semwal@linaro.org, tiwai@suse.com, tiwai@suse.de, tony.luck@intel.com, torvalds@linux-foundation.org, tzimmermann@suse.de, vbabka@suse.cz References: <20201215030350.xC0HoDUgG%akpm@linux-foundation.org> <2172e342-e73f-a759-fce5-8b94daafd506@amd.com> <20201215190840.GU4077@smile.fi.intel.com> From: =?UTF-8?Q?Christian_K=c3=b6nig?= Message-ID: <14a1a889-fc99-47df-c336-1727e8e22b42@amd.com> Date: Wed, 16 Dec 2020 08:47:25 +0100 User-Agent: Mozilla/5.0 (X11; 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Maybe we should >> note that here. > kmalloc()/kmalloc_array()/etc has the same. Should it be mentioned there as well? No, they don't. If kmalloc()/kmalloc_array() would ignore __GFP_ZERO we would have quite a problem. It is only krealloc()/krealloc_array() which ignore __GFP_ZERO when they don't reallocate memory because newsize is smaller than oldsize. In other words the freed up space is not cleared in any way. Christian.