Re: [PATCH v3 0/3] efi: Start tidying up memory management

["Vincent Stehlé" <vincent.stehle@arm.com>]

On Sun, Sep 01, 2024 at 04:22:56PM -0600, Simon Glass wrote:
> We have been discussing the state of EFI memory management for some
> years so I thought it might be best to send a short series showing some
> of the issues we have talked about.
> 
> This one just deals with memory allocation. It provides a way to detect
> EFI 'page allocations' when U-Boot' malloc() should be used. It should
> help us to clean up this area of U-Boot.
> 
> It also updates EFI to use U-Boot memory allocation for the pool. Most
> functions use that anyway and it is much more efficient. It also avoids
> allocating things 'in space' in conflict with the loaded images.

Hi Simon,

Thank you for this series.

I did test it on top of v2024.10-rc4 with AArch64 simulators (FVP & Qemu), with
OS boots and ACS-IR, and I see no regression. Same with sandbox on x86 and the
python tests.

Best regards,
Vincent.

> 
> This series also includes a little patch to show more information in
> the index for the EFI pages.
> 
> Note that this series is independent from Sugosh's lmb series[1],
> although I believe it will point the way to simplifying some of the
> later patches in that series.
> 
> Overall, some issues which should be resolved are:
> - allocation inconsistency, e.g. efi_add_protocol() uses malloc() but
>   efi_dp_dup() does not (this series makes a start)
> - change efi_bl_init() to register events later, when the devices are
>   actually used
> - rather than efi_set_bootdev(), provide a bootstd way to take note of
>   the device images came from and allow EFI to query that when needed
> - EFI_LOADER_BOUNCE_BUFFER - can use U-Boot bounce buffers?
> 
> Minor questions on my mind:
> - is unaligned access useful? Is there a performance penalty?
> - API confusion about whether something is an address or a pointer
> 
> [1] https://patchwork.ozlabs.org/project/uboot/list/?series=416441
> 
> Changes in v3:
> - Add new patch to drop the memset() from efi_alloc()
> - Drop patch to convert device_path allocation to use malloc()
> 
> Changes in v2:
> - Drop patch 'Show more information in efi index'
> - Drop patch 'Avoid pool allocation in efi_get_memory_map_alloc()'
> - Add the word 'warning', use log_warning() and show the end address
> 
> Simon Glass (3):
>   efi: Drop the memset() from efi_alloc()
>   efi: Allow use of malloc() for the EFI pool
>   efi: Show the location of the bounce buffer
> 
>  common/dlmalloc.c            |   7 +++
>  include/efi_loader.h         |  29 ++++++++-
>  include/malloc.h             |   7 +++
>  lib/efi_loader/efi_bootbin.c |  11 ++++
>  lib/efi_loader/efi_memory.c  | 119 ++++++++++++++++++++++++-----------
>  5 files changed, 136 insertions(+), 37 deletions(-)
> 
> -- 
> 2.34.1
>