package/boot/uboot-mvebu/patches/012-nvme-Do-not-allocate-8kB-buffer-on-stack.patch

   1 From d17ab6e1289b1d705c75de8a2351218962fb7352 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
   3 Date: Thu, 9 Dec 2021 11:06:39 +0100
   4 Subject: [PATCH] nvme: Do not allocate 8kB buffer on stack
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 Calling 'nvme scan' followed by 'nvme detail' crashes U-Boot on Turris
  10 Omnia with the following error:
  11
  12   undefined instruction
  13   pc : [<0a000000>]          lr : [<7ff80bfc>]
  14   reloc pc : [<8a8c0000>]    lr : [<00840bfc>]
  15   sp : 7fb2b908  ip : 0000002a     fp : 02000000
  16   r10: 04000000  r9 : 7fb2fed0     r8 : e1000000
  17   r7 : 0c000000  r6 : 03000000     r5 : 06000000  r4 : 01000000
  18   r3 : 7fb30928  r2 : 7fb30928     r1 : 00000000  r0 : 00000000
  19   Flags: nZCv  IRQs off  FIQs off  Mode SVC_32
  20   Code: 0f0fb4f0 0f0fb4f0 0f0fb4f0 0f0fb4f0 (f0f04b0f)
  21   Resetting CPU ...
  22
  23 This happens when nvme_print_info() tries to return to the caller. It
  24 looks like this error is caused by trying to allocate 8 KiB of memory
  25 on the stack by the two uses of ALLOC_CACHE_ALIGN_BUFFER().
  26
  27 Use malloc_cache_aligned() to allocate this memory dynamically instead.
  28
  29 This fixes 'nvme detail' on Turris Omnia.
  30
  31 Note that similar change was applied to file drivers/nvme/nvme.c in past by
  32 commit 2f83481dff9c ("nvme: use page-aligned buffer for identify command").
  33
  34 Signed-off-by: Pali Rohár <pali@kernel.org>
  35 Signed-off-by: Marek Behún <marek.behun@nic.cz>
  36 ---
  37  drivers/nvme/nvme_show.c | 35 ++++++++++++++++++++++++++---------
  38  1 file changed, 26 insertions(+), 9 deletions(-)
  39
  40 --- a/drivers/nvme/nvme_show.c
  41 +++ b/drivers/nvme/nvme_show.c
  42 @@ -106,24 +106,41 @@ int nvme_print_info(struct udevice *udev
  43  {
  44         struct nvme_ns *ns = dev_get_priv(udev);
  45         struct nvme_dev *dev = ns->dev;
  46 -       ALLOC_CACHE_ALIGN_BUFFER(char, buf_ns, sizeof(struct nvme_id_ns));
  47 -       struct nvme_id_ns *id = (struct nvme_id_ns *)buf_ns;
  48 -       ALLOC_CACHE_ALIGN_BUFFER(char, buf_ctrl, sizeof(struct nvme_id_ctrl));
  49 -       struct nvme_id_ctrl *ctrl = (struct nvme_id_ctrl *)buf_ctrl;
  50 +       struct nvme_id_ctrl *ctrl;
  51 +       struct nvme_id_ns *id;
  52 +       int ret = 0;
  53
  54 -       if (nvme_identify(dev, 0, 1, (dma_addr_t)(long)ctrl))
  55 -               return -EIO;
  56 +       ctrl = memalign(dev->page_size, sizeof(struct nvme_id_ctrl));
  57 +       if (!ctrl)
  58 +               return -ENOMEM;
  59 +
  60 +       if (nvme_identify(dev, 0, 1, (dma_addr_t)(long)ctrl)) {
  61 +               ret = -EIO;
  62 +               goto free_ctrl;
  63 +       }
  64
  65         print_optional_admin_cmd(le16_to_cpu(ctrl->oacs), ns->devnum);
  66         print_optional_nvm_cmd(le16_to_cpu(ctrl->oncs), ns->devnum);
  67         print_format_nvme_attributes(ctrl->fna, ns->devnum);
  68
  69 -       if (nvme_identify(dev, ns->ns_id, 0, (dma_addr_t)(long)id))
  70 -               return -EIO;
  71 +       id = memalign(dev->page_size, sizeof(struct nvme_id_ns));
  72 +       if (!id) {
  73 +               ret = -ENOMEM;
  74 +               goto free_ctrl;
  75 +       }
  76 +
  77 +       if (nvme_identify(dev, ns->ns_id, 0, (dma_addr_t)(long)id)) {
  78 +               ret = -EIO;
  79 +               goto free_id;
  80 +       }
  81
  82         print_formats(id, ns);
  83         print_data_protect_cap(id->dpc, ns->devnum);
  84         print_metadata_cap(id->mc, ns->devnum);
  85
  86 -       return 0;
  87 +free_id:
  88 +       free(id);
  89 +free_ctrl:
  90 +       free(ctrl);
  91 +       return ret;
  92  }