From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- drivers/mtd/lpddr/Kconfig | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100644 drivers/mtd/lpddr/Kconfig (limited to 'drivers/mtd/lpddr/Kconfig') diff --git a/drivers/mtd/lpddr/Kconfig b/drivers/mtd/lpddr/Kconfig new file mode 100644 index 000000000..0395aa6b6 --- /dev/null +++ b/drivers/mtd/lpddr/Kconfig @@ -0,0 +1,30 @@ +# SPDX-License-Identifier: GPL-2.0-only +menu "LPDDR & LPDDR2 PCM memory drivers" + depends on MTD + +config MTD_LPDDR + tristate "Support for LPDDR flash chips" + select MTD_QINFO_PROBE + help + This option enables support of LPDDR (Low power double data rate) + flash chips. Synonymous with Mobile-DDR. It is a new standard for + DDR memories, intended for battery-operated systems. + +config MTD_QINFO_PROBE + depends on MTD_LPDDR + tristate "Detect flash chips by QINFO probe" + help + Device Information for LPDDR chips is offered through the Overlay + Window QINFO interface, permits software to be used for entire + families of devices. This serves similar purpose of CFI on legacy + Flash products + +config MTD_LPDDR2_NVM + # ARM dependency is only for writel_relaxed() + depends on MTD && ARM + tristate "Support for LPDDR2-NVM flash chips" + help + This option enables support of PCM memories with a LPDDR2-NVM + (Low power double data rate 2) interface. + +endmenu -- cgit v1.3.1