uboot-mvebu: backport patch to fix nvme detail crash

Steps to reproduce:
1. Insert NVMe disk with a reduction to Turris Omnia
2. Go to U-boot
3. Run these two commands:
a) ``nvme scan``
b) ``nvme detail``
4. Wait for crash

This is backported from U-boot upstream repository.
It should be included in the upcoming release - 2022.04 [1].

It was tested on Turris Omnia, mvebu, cortex-a9, OpenWrt master.

[1] https://patchwork.ozlabs.org/project/uboot/patch/20211209100639.21530-1-pali@kernel.org/

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>
[Export the patch from U-Boot git]
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

diff --git a/package/boot/uboot-mvebu/patches/012-nvme-Do-not-allocate-8kB-buffer-on-stack.patch b/package/boot/uboot-mvebu/patches/012-nvme-Do-not-allocate-8kB-buffer-on-stack.patch
new file mode 100644 (file)
index 0000000..20046c6
--- /dev/null
+++ b/package/boot/uboot-mvebu/patches/012-nvme-Do-not-allocate-8kB-buffer-on-stack.patch
@@ -0,0 +1,92 @@
+From d17ab6e1289b1d705c75de8a2351218962fb7352 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
+Date: Thu, 9 Dec 2021 11:06:39 +0100
+Subject: [PATCH] nvme: Do not allocate 8kB buffer on stack
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Calling 'nvme scan' followed by 'nvme detail' crashes U-Boot on Turris
+Omnia with the following error:
+
+  undefined instruction
+  pc : [<0a000000>]          lr : [<7ff80bfc>]
+  reloc pc : [<8a8c0000>]    lr : [<00840bfc>]
+  sp : 7fb2b908  ip : 0000002a     fp : 02000000
+  r10: 04000000  r9 : 7fb2fed0     r8 : e1000000
+  r7 : 0c000000  r6 : 03000000     r5 : 06000000  r4 : 01000000
+  r3 : 7fb30928  r2 : 7fb30928     r1 : 00000000  r0 : 00000000
+  Flags: nZCv  IRQs off  FIQs off  Mode SVC_32
+  Code: 0f0fb4f0 0f0fb4f0 0f0fb4f0 0f0fb4f0 (f0f04b0f)
+  Resetting CPU ...
+
+This happens when nvme_print_info() tries to return to the caller. It
+looks like this error is caused by trying to allocate 8 KiB of memory
+on the stack by the two uses of ALLOC_CACHE_ALIGN_BUFFER().
+
+Use malloc_cache_aligned() to allocate this memory dynamically instead.
+
+This fixes 'nvme detail' on Turris Omnia.
+
+Note that similar change was applied to file drivers/nvme/nvme.c in past by
+commit 2f83481dff9c ("nvme: use page-aligned buffer for identify command").
+
+Signed-off-by: Pali Rohár <pali@kernel.org>
+Signed-off-by: Marek Behún <marek.behun@nic.cz>
+---
+ drivers/nvme/nvme_show.c | 35 ++++++++++++++++++++++++++---------
+ 1 file changed, 26 insertions(+), 9 deletions(-)
+
+--- a/drivers/nvme/nvme_show.c
++++ b/drivers/nvme/nvme_show.c
+@@ -106,24 +106,41 @@ int nvme_print_info(struct udevice *udev
+ {
+       struct nvme_ns *ns = dev_get_priv(udev);
+       struct nvme_dev *dev = ns->dev;
+-      ALLOC_CACHE_ALIGN_BUFFER(char, buf_ns, sizeof(struct nvme_id_ns));
+-      struct nvme_id_ns *id = (struct nvme_id_ns *)buf_ns;
+-      ALLOC_CACHE_ALIGN_BUFFER(char, buf_ctrl, sizeof(struct nvme_id_ctrl));
+-      struct nvme_id_ctrl *ctrl = (struct nvme_id_ctrl *)buf_ctrl;
++      struct nvme_id_ctrl *ctrl;
++      struct nvme_id_ns *id;
++      int ret = 0;
+ 
+-      if (nvme_identify(dev, 0, 1, (dma_addr_t)(long)ctrl))
+-              return -EIO;
++      ctrl = memalign(dev->page_size, sizeof(struct nvme_id_ctrl));
++      if (!ctrl)
++              return -ENOMEM;
++
++      if (nvme_identify(dev, 0, 1, (dma_addr_t)(long)ctrl)) {
++              ret = -EIO;
++              goto free_ctrl;
++      }
+ 
+       print_optional_admin_cmd(le16_to_cpu(ctrl->oacs), ns->devnum);
+       print_optional_nvm_cmd(le16_to_cpu(ctrl->oncs), ns->devnum);
+       print_format_nvme_attributes(ctrl->fna, ns->devnum);
+ 
+-      if (nvme_identify(dev, ns->ns_id, 0, (dma_addr_t)(long)id))
+-              return -EIO;
++      id = memalign(dev->page_size, sizeof(struct nvme_id_ns));
++      if (!id) {
++              ret = -ENOMEM;
++              goto free_ctrl;
++      }
++
++      if (nvme_identify(dev, ns->ns_id, 0, (dma_addr_t)(long)id)) {
++              ret = -EIO;
++              goto free_id;
++      }
+ 
+       print_formats(id, ns);
+       print_data_protect_cap(id->dpc, ns->devnum);
+       print_metadata_cap(id->mc, ns->devnum);
+ 
+-      return 0;
++free_id:
++      free(id);
++free_ctrl:
++      free(ctrl);
++      return ret;
+ }