1. 09 Apr, 2021 2 commits
  2. 08 Apr, 2021 2 commits
    • Mauro Carvalho Chehab's avatar
      media: venus: don't de-reference NULL pointers at IRQ time · 686ee9b6
      Mauro Carvalho Chehab authored
      Smatch is warning that:
      	drivers/media/platform/qcom/venus/hfi_venus.c:1100 venus_isr() warn: variable dereferenced before check 'hdev' (see line 1097)
      
      The logic basically does:
      	hdev = to_hfi_priv(core);
      
      with is translated to:
      	hdev = core->priv;
      
      If the IRQ code can receive a NULL pointer for hdev, there's
      a bug there, as it will first try to de-reference the pointer,
      and then check if it is null.
      
      After looking at the code, it seems that this indeed can happen:
      Basically, the venus IRQ thread is started with:
      	devm_request_threaded_irq()
      So, it will only be freed after the driver unbinds.
      
      In order to prevent the IRQ code to work with freed data,
      the logic at venus_hfi_destroy() sets core->priv to NULL,
      which would make the IRQ code to ignore any pending IRQs.
      
      There is, however a race condition, as core->priv is set
      to NULL only after being freed. So, we need also to move the
      core->priv = NULL to happen earlier.
      Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
      686ee9b6
    • Mauro Carvalho Chehab's avatar
      media: venus: use NULL instead of zero for pointers · b6f13994
      Mauro Carvalho Chehab authored
      As reported by sparse:
      
      	drivers/media/platform/qcom/venus/core.c:227:41: warning: Using plain integer as NULL pointer
      	drivers/media/platform/qcom/venus/core.c:228:34: warning: Using plain integer as NULL pointer
      
      Two vars are using zero instead of NULL for pointers. Not really
      an issue, but using NULL makes it clearer that the init data is
      expecting a pointer.
      Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
      b6f13994
  3. 07 Apr, 2021 2 commits
  4. 06 Apr, 2021 34 commits