Hi Simon, > -----Original Message----- > From: Simon Glass <[email protected]> > Sent: Wednesday, August 7, 2024 8:06 PM > To: Kummari, Prasad <[email protected]> > Cc: [email protected]; git (AMD-Xilinx) <[email protected]>; Simek, Michal > <[email protected]>; Abbarapu, Venkatesh > <[email protected]>; [email protected]; > [email protected]; [email protected]; [email protected] > Subject: Re: [PATCH] cmd: sf: prevent overwriting the reserved memory > > Caution: This message originated from an External Source. Use proper > caution when opening attachments, clicking links, or responding. > > > Hi Prasad, > > On Tue, 6 Aug 2024 at 23:05, Kummari, Prasad <[email protected]> wrote: > > > > Hi Glass, > > > > > -----Original Message----- > > > From: Simon Glass <[email protected]> > > > Sent: Wednesday, August 7, 2024 3:21 AM > > > To: Kummari, Prasad <[email protected]> > > > Cc: [email protected]; git (AMD-Xilinx) > <[email protected]>; Simek, > > > Michal <[email protected]>; Abbarapu, > Venkatesh > > > <[email protected]>; [email protected]; > > > [email protected]; [email protected]; [email protected] > > > Subject: Re: [PATCH] cmd: sf: prevent overwriting the reserved > > > memory > > > > > > Caution: This message originated from an External Source. Use proper > > > caution when opening attachments, clicking links, or responding. > > > > > > > > > Hi Prasad, > > > > > > On Tue, 6 Aug 2024 at 06:08, Prasad Kummari <[email protected]> > > > wrote: > > > > > > > > Added LMB API to prevent SF command from overwriting reserved > > > > memory areas. The current SPI code does not use LMB APIs for > > > > loading data into memory addresses. To resolve this, LMB APIs were > > > > added to check the load address of an SF command and ensure it > > > > does not overwrite reserved memory addresses. Similar checks are > > > > used in TFTP, serial load, and boot code to prevent overwriting reserved > memory. > > > > > > The SPI flash may be used to load other things, not just an OS. What > > > is your use case or problem here? > > > > [Prasad]: We have observed that SF command can overwrite the reserved > area without throwing any errors or warnings. > > This issue was noticed when the TF-A area is reserved in the Device > > Tree at address 0xf000000. The sf command is corrupting the reserved > area, and U-Boot relocation address too. > > > > EX: TF-A reserved at ddr address 0xf000000 > > > > Versal NET> sf read 0x0f000000 0x0 0x100 ----> Overwriting > > reserved > area. > > device 0 offset 0x0, size 0x100 > > SF: 256 bytes @ 0x0 Read: OK > > > > U-boot relocation address relocaddr = 0x000000007fec2000 > > > > Versal NET> sf write 0x0000000077ec2000 0x0 0x100 --> Overwriting > reserved area. > > device 0 offset 0x0, size 0x100 > > SF: 256 bytes @ 0x0 Written: OK > > Yes. There are many things which can overwrite memory, e.g. the mw > command. It is a boot loader so this is normal. > > What image are you loading here?
[Prasad] : We are loading TF-A(bl31.elf) at ddr address 0xf000000. > > Regards, > Simon
