Hi -
I recently brought in v 15 (and then v 17) of the CMA patches on tilt-tracking and backported to tilt-3.1 in order to support Panda onboard camera.
Without any highmem, stuff is working great, but with HIGHMEM, inclusion of either v15 and v17 CMA consistently blows chunks during DMA init like this -->
[ 0.517761] Enabling ERRATA 751472 [ 0.521392] OMAP4: Map 0xafe00000 to 0xfe600000 for dram barrier [ 0.529510] print_constraints: dummy: [ 0.534973] NET: Registered protocol family 16 [ 0.550659] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 0.559082] pgd = c0004000 [ 0.561950] [00000000] *pgd=00000000 [ 0.565734] Internal error: Oops: 805 [#1] PREEMPT SMP [ 0.571136] Modules linked in: [ 0.574371] CPU: 0 Tainted: G W (3.1.0-panda_tilt-3.1+ #2) [ 0.581268] PC is at __memzero+0x24/0x80 [ 0.585388] LR is at 0x0 [ 0.588073] pc : [<c0298ea4>] lr : [<00000000>] psr: 20000013 [ 0.588104] sp : ef833f54 ip : 00000000 fp : 00000000 [ 0.600067] r10: c0838c80 r9 : 00000000 r8 : 00000000 [ 0.605560] r7 : ef833f84 r6 : c14ac000 r5 : 00040000 r4 : 00000000 [ 0.612335] r3 : 00000000 r2 : 00000000 r1 : 0003ffc0 r0 : 00000000 [ 0.619140] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 0.626770] Control: 10c5387f Table: 8000404a DAC: 00000015 [ 0.632751] Process swapper (pid: 1, stack limit = 0xef8322f8) [ 0.638854] Stack: (0xef833f54 to 0xef834000) [ 0.643432] 3f40: c001df04 c0d3c000 00040000 [ 0.651947] 3f60: 00000647 c001dfa4 c08910a4 00040000 0000045f 00000000 00000000 c0838cc0 [ 0.660461] 3f80: 00000000 00000000 c08710cc c08ed640 ef832000 c0008900 0000009f c009e3c8 [ 0.668975] 3fa0: 0000009f c0838c80 c00145ec 00393531 00000000 c0140000 00000000 c08abcf4 [ 0.677459] 3fc0: 0000019a c08710cc c087186c c00145ec 00000013 00000000 00000000 00000000 [ 0.685974] 3fe0: 00000000 c0834874 00000000 00000000 c08347e8 c00145ec 37a42f33 10139e95 [ 0.694488] Code: e52de004 e1a0c002 e1a0e002 e2511040 (a8a0500c) [ 0.700866] ---[ end trace 1b75b31a2719ed1d ]--- [ 0.705749] Kernel panic - not syncing: Attempted to kill init! [ 0.711944] CPU1: stopping [ 0.714843] [<c001a524>] (unwind_backtrace+0x0/0xf8) from [<c000865c>] (do_IPI+0xf0/0x118) [ 0.723449] [<c000865c>] (do_IPI+0xf0/0x118) from [<c05d8ff4>] (__irq_svc+0x34/0xd0) [ 0.731506] Exception stack(0xef873f90 to 0xef873fd8) [ 0.736785] 3f80: ffffffed 00ce3000 ef873fd8 00000000 [ 0.745300] 3fa0: ef872000 c08ed704 c05e2a8c c0890754 c0890914 411fc092 00000000 00000000 [ 0.753814] 3fc0: 00000001 ef873fd8 c0014648 c001464c 60000113 ffffffff [ 0.760742] [<c05d8ff4>] (__irq_svc+0x34/0xd0) from [<c001464c>] (default_idle+0x24/0x28) [ 0.769256] [<c001464c>] (default_idle+0x24/0x28) from [<c001489c>] (cpu_idle+0xfc/0x11c) [ 0.777770] [<c001489c>] (cpu_idle+0xfc/0x11c) from [<805d1954>] (0x805d1954)
Is it expected CMA and high memory should work OK? I see there's a note in the CMA log about "implement support for contiguous memory areas placed in HIGHMEM zone", but it's ambiguous if it should be ignoring highmem or is expected to blow chunks.
If it's expected to blow chunks, is there a hack or workaround that will allow us to have both HIGHMEM and CMA on OMAP4?
-Andy