In the Linux kernel, the following vulnerability has been resolved: usb: cdns3: fix random warning message when driver load Warning log: [ 4.141392] Unexpected gfp: 0x4 (GFPDMA32). Fixing up to gfp: 0xa20 (GFPATOMIC). Fix your code! [ 4.150340] CPU: 1 PID: 175 Comm: 1-0050 Not tainted 5.15.5-00039-g2fd9ae1b568c #20 [ 4.158010] Hardware name: Freescale i.MX8QXP MEK (DT) [ 4.163155] Call trace: [ 4.165600] dumpbacktrace+0x0/0x1b0 [ 4.169286] showstack+0x18/0x68 [ 4.172611] dumpstacklvl+0x68/0x84 [ 4.176286] dumpstack+0x18/0x34 [ 4.179613] kmallocfixflags+0x60/0x88 [ 4.183550] newslab+0x334/0x370 [ 4.186878] _slaballoc.part.108+0x4d4/0x748 [ 4.191419] _slaballoc.isra.109+0x30/0x78 [ 4.195702] kmemcachealloc+0x40c/0x420 [ 4.199725] dmapoolalloc+0xac/0x1f8 [ 4.203486] cdns3allocatetrbpool+0xb4/0xd0 poolallocpage(struct dmapool *pool, gfpt memflags) { ... page = kmalloc(sizeof(*page), memflags); page->vaddr = dmaalloccoherent(pool->dev, pool->allocation, &page->dma, memflags); ... } kmalloc was called with memflags, which is passed down in cdns3allocatetrbpool() and have GFPDMA32 flags. kmallfixflags() report warning. GFPDMA32 is not useful at all. dmaalloccoherent() will handle DMA memory region correctly by pool->dev. GFPDMA32 can be removed safely.