usb: host: Fix excessive alignment restriction for local memory allocations (ff2437be) · Commits · 戴 / test

The PAGE_SHIFT alignment restriction to devm_gen_pool_create() quickly exhaust local memory because most allocations are much smaller than PAGE_SIZE. This causes USB device failures such as usb 1-2.1: reset full-speed USB device number 4 using sm501-usb sd 1:0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x03 driverbyte=0x00 sd 1:0:0:0: [sda] tag#0 CDB: opcode=0x28 28 00 00 00 08 7c 00 00 f0 00 print_req_error: I/O error, dev sda, sector 2172 flags 80700 when trying to boot from the SM501 USB controller on SH4 with QEMU. Align allocations as required but not necessarily much more than that. The HCCA, TD and ED structures align with 256, 32 and 16 byte memory boundaries, as specified by the Open HCI[1]. The min_alloc_order argument to devm_gen_pool_create is now somewhat arbitrarily set to 4 (16 bytes). Perhaps it could be somewhat lower for general buffer allocations. Reference: [1] "Open Host Controller Interface Specification for USB", release 1.0a, Compaq, Microsoft, National Semiconductor, 1999, pp. 16, 19, 33. Reported-by:

Guenter Roeck <linux@roeck-us.net> Signed-off-by:

Fredrik Noring <noring@nocrew.org> Tested-by:

Guenter Roeck <linux@roeck-us.net> Signed-off-by:

Christoph Hellwig <hch@lst.de>

drivers/usb/core/hcd.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -3044,7 +3044,7 @@ int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
		int err;
		void *local_mem;

		hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, PAGE_SHIFT,
		hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
		dev_to_node(hcd->self.sysdev),
		dev_name(hcd->self.sysdev));
		if (IS_ERR(hcd->localmem_pool))

drivers/usb/host/ohci-hcd.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -507,9 +507,9 @@ static int ohci_init (struct ohci_hcd *ohci)
		ohci->prev_frame_no = IO_WATCHDOG_OFF;

		if (hcd->localmem_pool)
		ohci->hcca = gen_pool_dma_alloc(hcd->localmem_pool,
		ohci->hcca = gen_pool_dma_alloc_align(hcd->localmem_pool,
		sizeof(*ohci->hcca),
		&ohci->hcca_dma);
		&ohci->hcca_dma, 256);
		else
		ohci->hcca = dma_alloc_coherent(hcd->self.controller,
		sizeof(*ohci->hcca),

drivers/usb/host/ohci-mem.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -94,7 +94,8 @@ td_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
		struct usb_hcd *hcd = ohci_to_hcd(hc);

		if (hcd->localmem_pool)
		td = gen_pool_dma_zalloc(hcd->localmem_pool, sizeof(*td), &dma);
		td = gen_pool_dma_zalloc_align(hcd->localmem_pool,
		sizeof(*td), &dma, 32);
		else
		td = dma_pool_zalloc(hc->td_cache, mem_flags, &dma);
		if (td) {
		@@ -137,7 +138,8 @@ ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
		struct usb_hcd *hcd = ohci_to_hcd(hc);

		if (hcd->localmem_pool)
		ed = gen_pool_dma_zalloc(hcd->localmem_pool, sizeof(*ed), &dma);
		ed = gen_pool_dma_zalloc_align(hcd->localmem_pool,
		sizeof(*ed), &dma, 16);
		else
		ed = dma_pool_zalloc(hc->ed_cache, mem_flags, &dma);
		if (ed) {

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