On Tue, Apr 16, 2024 at 05:52:58PM +0530, Chintan Vankar wrote: > > > On 12/04/24 03:37, Tom Rini wrote: > > On Wed, Apr 03, 2024 at 06:18:01PM +0530, Chintan Vankar wrote: > > > > > > > > > On 22/01/24 10:11, Siddharth Vadapalli wrote: > > > > > > > > > > > > On 20/01/24 22:11, Tom Rini wrote: > > > > > On Mon, Jan 15, 2024 at 01:42:51PM +0530, Siddharth Vadapalli wrote: > > > > > > Hello Tom, > > > > > > > > > > > > On 12/01/24 18:56, Tom Rini wrote: > > > > > > > > ... > > > > > > > > > > > The list of conditionals in common/spl/spl.c::board_init_r() > > > > > > > should be > > > > > > > updated and probably use SPL_NET as the option to check for. > > > > > > > > > > > > Thank you for reviewing the patch and pointing this out. I wasn't > > > > > > aware of it. I > > > > > > assume that you are referring to the following change: > > > > > > > > > > > > if (IS_ENABLED(CONFIG_SPL_OS_BOOT) || > > > > > > CONFIG_IS_ENABLED(HANDOFF) || > > > > > > - IS_ENABLED(CONFIG_SPL_ATF)) > > > > > > + IS_ENABLED(CONFIG_SPL_ATF) || > > > > > > IS_ENABLED(CONFIG_SPL_NET)) > > > > > > dram_init_banksize(); > > > > > > > > > > > > I shall replace the current patch with the above change in the v2 > > > > > > series. Since > > > > > > this is in the common section, is there a generic reason I could > > > > > > provide in the > > > > > > commit message rather than the existing commit message which seems > > > > > > to be board > > > > > > specific? Also, I hope that the above change will not cause > > > > > > regressions for > > > > > > other non-TI devices. Please let me know. > > > > > > > > > > Yes, that's the area, and just note that networking also requires the > > > > > DDR to be initialized. > > > > > > > > > > > > > Thank you for confirming and providing your suggestion for the contents > > > > of the > > > > commit message. > > > > > > > Following Tom's Suggestion of adding CONFIG_SPL_NET in common/spl/spl.c > > > "dram_init_banksize()", the issue of fetching a file at SPL stage seemed > > > to be fixed. However the commit "ba20b2443c29", which sets gd->ram_top > > > for the very first time in "spl_enable_cache()" results in > > > "arch_lmb_reserve()" function reserving memory region from Stack pointer > > > at "0x81FFB820" to gd->ram_top pointing to "0x100000000". Previously > > > when gd->ram_top was zero "arch_lmb_reserve()" was noop. Now using TFTP > > > to fetch U-Boot image at SPL stage results in "tftp_init_load_addr()" > > > function call that invokes "arch_lmb_reserve()" function, which reserves > > > entire memory starting from Stack Pointer to gd->ram_top leaving no > > > space to load U-Boot image via TFTP since TFTP loads files at pre > > > configured memory address at "0x82000000". > > > > > > As a workaround for this issue, one solution we can propose is to > > > disable the checks "lmb_get_free_size()" at SPL and U-Boot stage. For > > > that we can define a new config option for LMB reserve checks as > > > "SPL_LMB". This config will be enable by default for the backword > > > compatibility and disable for our use case at SPL and U-Boot stage. > > > > The problem here is that we need LMB for booting an OS, which is > > something we'll want in SPL in non-cortex-R cases too, which means this > > platform, so that's a no-go. I think you need to dig harder and see if > > you can correct the logic somewhere so that we don't over reserve? > > > Since this issue is due to function call "lmb_init_and_reserve()" > function invoked from "tftp_init_load_addr()" function. This function > is defined by Simon in commit "a156c47e39ad", which fixes > "CVE-2018-18439" to prevent overwriting reserved memory. Simon, can you > explain why do we need to call "lmb_init_and_reserve()" function here ?
This is indeed a tricky area which is why Sughosh is looking in to trying to re-work the LMB mechanic and we've had a few long threads about it as well. I've honestly forgotten the use case you have here, can you please remind us? -- Tom
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