Description of problem:

When I try to boot with a large (499342536 B) initrd on UEFI, Grub prints the error "can't allocate initrd" and the kernel then panics (it can't find root)

Version-Release number of selected component (if applicable):
1:2.02-142.el8_7.3

How reproducible:
Easily at least on a HP ProLiant DL180 Gen9 with a large initrd (I can provide one) and console access

Steps to Reproduce:
1. boot to the GRUB prompt
2. linux /rear/EFI/BOOT/kernel console=ttyS0,115200
3. initrd /rear/EFI/BOOT/initrd.cgz

Actual results:
error: ../../grub-core/loader/i386/efi/linux.c:158:can't allocate initrd.

Expected results:
initrd gets loaded and I can boot

Additional info:
A similar bug was reported as bz2048433 and now it looks that it has reappeared.
I tried grub2-2.02-121.el8, works fine, so it is a regression.

Memory information from EFI shell

Shell> memmap
Type Start End # Pages Attributes
BS_Code 0000000000000000-0000000000000FFF 0000000000000001 000000000000000F
Available 0000000000001000-0000000000057FFF 0000000000000057 000000000000000F
BS_Code 0000000000058000-0000000000092FFF 000000000000003B 000000000000000F
BS_Data 0000000000093000-0000000000093FFF 0000000000000001 000000000000000F
BS_Code 0000000000094000-000000000009FFFF 000000000000000C 000000000000000F
Available 0000000000100000-0000000007FFFFFF 0000000000007F00 000000000000000F
BS_Code 0000000008000000-000000000FFFFFFF 0000000000008000 000000000000000F
Available 0000000010000000-000000003ECFFFFF 000000000002ED00 000000000000000F
BS_Data 000000003ED00000-000000003ED7FFFF 0000000000000080 000000000000000F
Available 000000003ED80000-000000005A6A0FFF 000000000001B921 000000000000000F
Reserved 000000005A6A1000-000000005B4A0FFF 0000000000000E00 000000000000000F
BS_Data 000000005B4A1000-000000006ECFAFFF 000000000001385A 000000000000000F
BS_Code 000000006ECFB000-000000006ECFBFFF 0000000000000001 000000000000000F
Available 000000006ECFC000-0000000070CD1FFF 0000000000001FD6 000000000000000F
BS_Data 0000000070CD2000-0000000070EBEFFF 00000000000001ED 000000000000000F
Available 0000000070EBF000-000000007100BFFF 000000000000014D 000000000000000F
BS_Data 000000007100C000-0000000071047FFF 000000000000003C 000000000000000F
Available 0000000071048000-0000000071055FFF 000000000000000E 000000000000000F
BS_Data 0000000071056000-0000000071072FFF 000000000000001D 000000000000000F
Available 0000000071073000-0000000071075FFF 0000000000000003 000000000000000F
BS_Data 0000000071076000-000000007107CFFF 0000000000000007 000000000000000F
Available 000000007107D000-000000007107FFFF 0000000000000003 000000000000000F
BS_Data 0000000071080000-0000000076CFEFFF 0000000000005C7F 000000000000000F
Available 0000000076CFF000-00000000772D1FFF 00000000000005D3 000000000000000F
LoaderCode 00000000772D2000-00000000774FEFFF 000000000000022D 000000000000000F
Available 00000000774FF000-00000000777ECFFF 00000000000002EE 000000000000000F
BS_Code 00000000777ED000-00000000784FEFFF 0000000000000D12 000000000000000F
RT_Data 00000000784FF000-00000000788FEFFF 0000000000000400 800000000000000F
RT_Code 00000000788FF000-00000000790FEFFF 0000000000000800 800000000000000F
Reserved 00000000790FF000-00000000791FEFFF 0000000000000100 000000000000000F
ACPI_NVS 00000000791FF000-000000007B5FEFFF 0000000000002400 000000000000000F
ACPI_Recl 000000007B5FF000-000000007B7FEFFF 0000000000000200 000000000000000F
BS_Data 000000007B7FF000-000000007B7FFFFF 0000000000000001 000000000000000F
Available 0000000100000000-000000047FFFFFFF 0000000000380000 000000000000000F
MMIO 0000000080000000-000000008FFFFFFF 0000000000010000 8000000000000000

Reserved : 3,840 Pages (15,728,640 Bytes)
LoaderCode: 557 Pages (2,281,472 Bytes)
LoaderData: 0 Pages (0 Bytes)
BS_Code : 36,187 Pages (148,221,952 Bytes)
BS_Data : 104,360 Pages (427,458,560 Bytes)
RT_Code : 2,048 Pages (8,388,608 Bytes)
RT_Data : 1,024 Pages (4,194,304 Bytes)
ACPI_Recl : 512 Pages (2,097,152 Bytes)
ACPI_NVS : 9,216 Pages (37,748,736 Bytes)
MMIO es (0 Bytes)
PalCode : 0 Pages (0 Bytes)
Available : 4,018,032 Pages (16,457,859,072 Bytes)
Persistent: 0 Pages (0 Bytes)
--------------
Total Memory: 16,296 MB (17,088,249,856 Bytes)
Shell> : 65,536 Pages (268,435,456 Bytes)
MMIO_Port : 0 Pag

memory information from GRUB2 1:2.02-142.el8_7.3

grub> lsefimmap
Type Physical start - end #Pages Size Attributes
BS-code 0000000000000000-0000000000000fff 00000001 4KiB UC WC WT WB
conv-mem 0000000000001000-0000000000057fff 00000057 348KiB UC WC WT WB
BS-code 0000000000058000-0000000000092fff 0000003b 236KiB UC WC WT WB
BS-data 0000000000093000-0000000000093fff 00000001 4KiB UC WC WT WB
BS-code 0000000000094000-000000000009ffff 0000000c 48KiB UC WC WT WB
conv-mem 0000000000100000-0000000007ffffff 00007f00 127MiB UC WC WT WB
BS-code 0000000008000000-000000000fffffff 00008000 128MiB UC WC WT WB
conv-mem 0000000010000000-0000000029932fff 00019933 419020KiB UC WC WT WB
ldr-code 0000000029933000-000000003ecfffff 000153cd 347956KiB UC WC WT WB
BS-data 000000003ed00000-000000003ed7ffff 00000080 512KiB UC WC WT WB
conv-mem 000000003ed80000-000000005a6a0fff 0001b921 451716KiB UC WC WT WB
reserved 000000005a6a1000-000000005b4a0fff 00000e00 14MiB UC WC WT WB
BS-data 000000005b4a1000-000000006ecfafff 0001385a 319848KiB UC WC WT WB
BS-code 000000006ecfb000-000000006ecfbfff 00000001 4KiB UC WC WT WB
conv-mem 000000006ecfc000-000000007114efff 00002453 37196KiB UC WC WT WB
BS-data 000000007114f000-0000000071524fff 000003d6 3928KiB UC WC WT WB
conv-mem 0000000071525000-0000000071535fff 00000011 68KiB UC WC WT WB
BS-data 0000000071536000-000000007156dfff 00000038 224KiB UC WC WT WB
conv-mem 000000007156e000-000000007156ffff 00000002 8KiB UC WC WT WB
BS-data 0000000071570000-0000000071572fff 00000003 12KiB UC WC WT WB
conv-mem 0000000071573000-0000000071573fff 00000001 4KiB UC WC WT WB
BS-data 0000000071574000-0000000071582fff 0000000f 60KiB UC WC WT WB
conv-mem 0000000071583000-0000000071585fff 00000003 12KiB UC WC WT WB
BS-data 0000000071586000-0000000071591fff 0000000c 48KiB UC WC WT WB
conv-mem 0000000071592000-0000000071592fff 00000001 4KiB UC WC WT WB
BS-data 0000000071593000-0000000071f1dfff 0000098b 9772KiB UC WC WT WB
conv-mem 0000000071f1e000-0000000071f1efff 00000001 4KiB UC WC WT WB
BS-data 0000000071f1f000-0000000071f33fff 00000015 84KiB UC WC WT WB
conv-mem 0000000071f34000-0000000071f34fff 00000001 4KiB UC WC WT WB
BS-data 0000000071f35000-0000000071f35fff 00000001 4KiB UC WC WT WB
conv-mem 0000000071f36000-0000000071f36fff 00000001 4KiB UC WC WT WB
BS-data 0000000071f37000-0000000076cfefff 00004dc8 79648KiB UC WC WT WB
conv-mem 0000000076cff000-0000000076edbfff 000001dd 1908KiB UC WC WT WB
ldr-data 0000000076edc000-00000000770fcfff 00000221 2180KiB UC WC WT WB
conv-mem 00000000770fd000-00000000771dcfff 000000e0 896KiB UC WC WT WB
ldr-code 00000000771dd000-00000000774fefff 00000322 3208KiB UC WC WT WB
conv-mem 00000000774ff000-00000000777ecfff 000002ee 3000KiB UC WC WT WB
BS-code 00000000777ed000-00000000784fefff 00000d12 13384KiB UC WC WT WB
RT-data 00000000784ff000-00000000788fefff 00000400 4MiB RT UC WC WT WB
RT-code 00000000788ff000-00000000790fefff 00000800 8MiB RT UC WC WT WB
reserved 00000000790ff000-00000000791fefff 00000100 1MiB UC WC WT WB
ACPI-nvs 00000000791ff000-000000007b5fefff 00002400 36MiB UC WC WT WB
ACPI-rec 000000007b5ff000-000000007b7fefff 00000200 2MiB UC WC WT WB
BS-data 000000007b7ff000-000000007b7fffff 00000001 4KiB UC WC WT WB
conv-mem 0000000100000000-000000047fffffff 00380000 14GiB UC WC WT WB
MMIO 0000000080000000-000000008fffffff 00010000 256MiB RT

memory information from grub2-2.02-121.el8 (good)

grub> lsefimmap
Type Physical start - end #Pages Size Attributes
BS-code 0000000000000000-0000000000000fff 00000001 4KiB UC WC WT WB
conv-mem 0000000000001000-0000000000057fff 00000057 348KiB UC WC WT WB
BS-code 0000000000058000-0000000000092fff 0000003b 236KiB UC WC WT WB
BS-data 0000000000093000-0000000000093fff 00000001 4KiB UC WC WT WB
BS-code 0000000000094000-000000000009ffff 0000000c 48KiB UC WC WT WB
conv-mem 0000000000100000-0000000007ffffff 00007f00 127MiB UC WC WT WB
BS-code 0000000008000000-000000000fffffff 00008000 128MiB UC WC WT WB
conv-mem 0000000010000000-0000000029a51fff 00019a52 420168KiB UC WC WT WB
ldr-code 0000000029a52000-000000003ecfffff 000152ae 346808KiB UC WC WT WB
BS-data 000000003ed00000-000000003ed7ffff 00000080 512KiB UC WC WT WB
conv-mem 000000003ed80000-000000004a009fff 0000b28a 182824KiB UC WC WT WB
ldr-code 000000004a00a000-000000005a6a0fff 00010697 268892KiB UC WC WT WB
reserved 000000005a6a1000-000000005b4a0fff 00000e00 14MiB UC WC WT WB
BS-data 000000005b4a1000-000000006ecfafff 0001385a 319848KiB UC WC WT WB
BS-code 000000006ecfb000-000000006ecfbfff 00000001 4KiB UC WC WT WB
conv-mem 000000006ecfc000-0000000070cd1fff 00001fd6 32600KiB UC WC WT WB
BS-data 0000000070cd2000-0000000070ebefff 000001ed 1972KiB UC WC WT WB
conv-mem 0000000070ebf000-0000000071098fff 000001da 1896KiB UC WC WT WB
BS-data 0000000071099000-000000007109bfff 00000003 12KiB UC WC WT WB
conv-mem 000000007109c000-00000000710abfff 00000010 64KiB UC WC WT WB
BS-data 00000000710ac000-0000000071409fff 0000035e 3448KiB UC WC WT WB
conv-mem 000000007140a000-000000007141ffff 00000016 88KiB UC WC WT WB
BS-data 0000000071420000-0000000071422fff 00000003 12KiB UC WC WT WB
conv-mem 0000000071423000-0000000071426fff 00000004 16KiB UC WC WT WB
BS-data 0000000071427000-00000000714f6fff 000000d0 832KiB UC WC WT WB
conv-mem 00000000714f7000-00000000714f9fff 00000003 12KiB UC WC WT WB
BS-data 00000000714fa000-0000000071504fff 0000000b 44KiB UC WC WT WB
conv-mem 0000000071505000-0000000071506fff 00000002 8KiB UC WC WT WB
BS-data 0000000071507000-0000000071507fff 00000001 4KiB UC WC WT WB
conv-mem 0000000071508000-0000000071508fff 00000001 4KiB UC WC WT WB
BS-data 0000000071509000-0000000076cfefff 000057f6 90072KiB UC WC WT WB
conv-mem 0000000076cff000-00000000770f7fff 000003f9 4068KiB UC WC WT WB
ldr-data 00000000770f8000-00000000770f8fff 00000001 4KiB UC WC WT WB
conv-mem 00000000770f9000-00000000774befff 000003c6 3864KiB UC WC WT WB
ldr-code 00000000774bf000-00000000774fefff 00000040 256KiB UC WC WT WB
conv-mem 00000000774ff000-00000000777ecfff 000002ee 3000KiB UC WC WT WB
BS-code 00000000777ed000-00000000784fefff 00000d12 13384KiB UC WC WT WB
RT-data 00000000784ff000-00000000788fefff 00000400 4MiB RT UC WC WT WB
RT-code 00000000788ff000-00000000790fefff 00000800 8MiB RT UC WC WT WB
reserved 00000000790ff000-00000000791fefff 00000100 1MiB UC WC WT WB
ACPI-nvs 00000000791ff000-000000007b5fefff 00002400 36MiB UC WC WT WB
ACPI-rec 000000007b5ff000-000000007b7fefff 00000200 2MiB UC WC WT WB
BS-data 000000007b7ff000-000000007b7fffff 00000001 4KiB UC WC WT WB
conv-mem 0000000100000000-000000047fffffff 00380000 14GiB UC WC WT WB
MMIO 0000000080000000-000000008fffffff 00010000 256MiB RT