In the case where lmem_size < dsm_base, hardware is reporting that
stolen lmem is unusable. In this case, instead of throwing a warning,
we can continue execution as normal by disabling stolen LMEM support.
For example, this change will allow the following error report from
ATS-M to no longer apply:
<6> [144.859887] pcieport :4b:00.0: bridge window [mem
0xb100-0xb11f]
<6> [144.859900] pcieport :4b:00.0: bridge window [mem
0x3bbc-0x3bbc17ff 64bit pref]
<6> [144.859917] pcieport :4c:01.0: PCI bridge to [bus 4d-4e]
<6> [144.859932] pcieport :4c:01.0: bridge window [mem
0xb100-0xb11f]
<6> [144.859945] pcieport :4c:01.0: bridge window [mem
0x3bbc-0x3bbc17ff 64bit pref]
<6> [144.859984] i915 :4d:00.0: [drm] BAR2 resized to 256M
<6> [144.860640] i915 :4d:00.0: [drm] Using a reduced BAR size of 256MiB.
Consider enabling 'Resizable BAR' or similar, if available in the BIOS.
<4> [144.860719] ---[ cut here ]---
<4> [144.860727] WARNING: CPU: 17 PID: 1815 at
drivers/gpu/drm/i915/gem/i915_gem_stolen.c:939
i915_gem_stolen_lmem_setup+0x38c/0x430 [i915]
<4> [144.861430] Modules linked in: i915 snd_intel_dspcfg snd_hda_codec
snd_hwdep snd_hda_core snd_pcm vgem drm_shmem_helper prime_numbers i2c_algo_bit
ttm video drm_display_helper drm_buddy fuse x86_pkg_temp_thermal coretemp
kvm_intel kvm ixgbe mdio irqbypass ptp crct10dif_pclmul crc32_pclmul
ghash_clmulni_intel pps_core i2c_i801 mei_me i2c_smbus mei wmi acpi_power_meter
[last unloaded: i915]
<4> [144.861611] CPU: 17 PID: 1815 Comm: i915_module_loa Tainted: G U
6.8.0-rc5-drmtip_1515-g78f49af27723+ #1
<4> [144.861624] Hardware name: Intel Corporation WHITLEY/WHITLEY, BIOS
SE5C6200.86B.0020.P41.2109300305 09/30/2021
<4> [144.861632] RIP: 0010:i915_gem_stolen_lmem_setup+0x38c/0x430 [i915]
<4> [144.862287] Code: ff 41 c1 e4 05 e9 ac fe ff ff 4d 63 e4 48 89 ef 48 85 ed
74 04 48 8b 7d 08 48 c7 c6 10 a3 7b a0 e8 e9 90 43 e1 e9 ee fd ff ff <0f> 0b 49
c7 c4 ed ff ff ff e9 e0 fd ff ff 0f b7 d2 48 c7 c6 00 d9
<4> [144.862299] RSP: 0018:c90005607980 EFLAGS: 00010207
<4> [144.862315] RAX: fff0 RBX: 0003 RCX:
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/10833
Suggested-by: Chris Wilson
Signed-off-by: Jonathan Cavitt
---
v2:
- Return 0 to allow execution to continue
- Remove white space in commit message
- s/Fixes/Closes
drivers/gpu/drm/i915/gem/i915_gem_stolen.c | 8 ++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
index ad6dd7f3259bc..4d60a5b375053 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
@@ -936,8 +936,12 @@ i915_gem_stolen_lmem_setup(struct drm_i915_private *i915,
u16 type,
} else {
/* Use DSM base address instead for stolen memory */
dsm_base = intel_uncore_read64(uncore, GEN6_DSMBASE) &
GEN11_BDSM_MASK;
- if (WARN_ON(lmem_size < dsm_base))
- return ERR_PTR(-ENODEV);
+ if (lmem_size < dsm_base) {
+ drm_dbg(>drm,
+ "Disabling stolen memory support due to OOB
placement: lmem_size = %lli vs dsm_base = %lli\n",
+ lmem_size, dsm_base);
+ return 0;
+ }
dsm_size = ALIGN_DOWN(lmem_size - dsm_base, SZ_1M);
}
--
2.25.1
