selftests/bpf: Test rhtab kptr cancellation semanticsgrafted

Resizable hash-map updates and deletions must not perform full special-field
destruction in their caller context. In particular, a referenced kptr must
remain attached to the allocation until the memory allocator destructor can
release it safely.

Add separate coverage for both affected paths. The update test stores a task
kptr, replaces the ordinary value bytes with BPF_EXIST, and verifies that the
kptr survived. The delete test removes an element and exchanges its kptr
through the still-valid map-value pointer before the allocation is reclaimed.

Both cases observe a NULL kptr when rhtab uses bpf_obj_free_fields(). They
recover and release the reference after rhtab switches to cancellation
semantics.

Signed-off-by: Nuoqi Gui <gnq25@mails.tsinghua.edu.cn>
[ kkd: Split update and delete coverage and rewrote the commit log ]
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260904104203.345917-5-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 98 insertions, 0 deletions

diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
new file mode 100644
index 000000000..b46376af6
--- /dev/null
+++ b/drivers/clocksource/Makefile
@@ -0,0 +1,98 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_TIMER_OF)		+= timer-of.o
+obj-$(CONFIG_TIMER_PROBE)	+= timer-probe.o
+obj-$(CONFIG_ATMEL_PIT)		+= timer-atmel-pit.o
+obj-$(CONFIG_ATMEL_ST)		+= timer-atmel-st.o
+obj-$(CONFIG_ATMEL_TCB_CLKSRC)	+= timer-atmel-tcb.o
+obj-$(CONFIG_X86_PM_TIMER)	+= acpi_pm.o
+obj-$(CONFIG_SCx200HR_TIMER)	+= scx200_hrt.o
+obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC)	+= timer-cs5535.o
+obj-$(CONFIG_CLKSRC_JCORE_PIT)		+= jcore-pit.o
+obj-$(CONFIG_SH_TIMER_CMT)	+= sh_cmt.o
+obj-$(CONFIG_SH_TIMER_MTU2)	+= sh_mtu2.o
+obj-$(CONFIG_RENESAS_OSTM)	+= renesas-ostm.o
+obj-$(CONFIG_SH_TIMER_TMU)	+= sh_tmu.o
+obj-$(CONFIG_EM_TIMER_STI)	+= em_sti.o
+obj-$(CONFIG_CLKBLD_I8253)	+= i8253.o
+obj-$(CONFIG_CLKSRC_MMIO)	+= mmio.o
+obj-$(CONFIG_DAVINCI_TIMER)	+= timer-davinci.o
+obj-$(CONFIG_DIGICOLOR_TIMER)	+= timer-digicolor.o
+obj-$(CONFIG_ECONET_EN751221_TIMER)	+= timer-econet-en751221.o
+obj-$(CONFIG_OMAP_DM_TIMER)	+= timer-ti-dm.o
+obj-$(CONFIG_OMAP_DM_SYSTIMER)	+= timer-ti-dm-systimer.o
+obj-$(CONFIG_DW_APB_TIMER)	+= dw_apb_timer.o
+obj-$(CONFIG_DW_APB_TIMER_OF)	+= dw_apb_timer_of.o
+obj-$(CONFIG_FTTMR010_TIMER)	+= timer-fttmr010.o
+obj-$(CONFIG_IXP4XX_TIMER)	+= timer-ixp4xx.o
+obj-$(CONFIG_ROCKCHIP_TIMER)      += timer-rockchip.o
+obj-$(CONFIG_CLKSRC_NOMADIK_MTU)	+= nomadik-mtu.o
+obj-$(CONFIG_CLKSRC_DBX500_PRCMU)	+= clksrc-dbx500-prcmu.o
+obj-$(CONFIG_ARMADA_370_XP_TIMER)	+= timer-armada-370-xp.o
+obj-$(CONFIG_ORION_TIMER)	+= timer-orion.o
+obj-$(CONFIG_BCM2835_TIMER)	+= bcm2835_timer.o
+obj-$(CONFIG_CLPS711X_TIMER)	+= clps711x-timer.o
+obj-$(CONFIG_MXS_TIMER)		+= mxs_timer.o
+obj-$(CONFIG_CLKSRC_PXA)	+= timer-pxa.o
+obj-$(CONFIG_SUN4I_TIMER)	+= timer-sun4i.o
+obj-$(CONFIG_SUN5I_HSTIMER)	+= timer-sun5i.o
+obj-$(CONFIG_MESON6_TIMER)	+= timer-meson6.o
+obj-$(CONFIG_TEGRA_TIMER)	+= timer-tegra.o
+obj-$(CONFIG_TEGRA186_TIMER)	+= timer-tegra186.o
+obj-$(CONFIG_VT8500_TIMER)	+= timer-vt8500.o
+obj-$(CONFIG_NSPIRE_TIMER)	+= timer-zevio.o
+obj-$(CONFIG_BCM_KONA_TIMER)	+= bcm_kona_timer.o
+obj-$(CONFIG_CADENCE_TTC_TIMER)	+= timer-cadence-ttc.o
+obj-$(CONFIG_CLKSRC_STM32)	+= timer-stm32.o
+obj-$(CONFIG_CLKSRC_STM32_LP)	+= timer-stm32-lp.o
+obj-$(CONFIG_CLKSRC_EXYNOS_MCT)	+= exynos_mct.o
+obj-$(CONFIG_CLKSRC_LPC32XX)	+= timer-lpc32xx.o
+obj-$(CONFIG_CLKSRC_MPS2)	+= mps2-timer.o
+obj-$(CONFIG_CLKSRC_SAMSUNG_PWM)	+= samsung_pwm_timer.o
+obj-$(CONFIG_FSL_FTM_TIMER)	+= timer-fsl-ftm.o
+obj-$(CONFIG_NXP_PIT_TIMER)	+= timer-nxp-pit.o
+obj-$(CONFIG_CLKSRC_QCOM)	+= timer-qcom.o
+obj-$(CONFIG_MTK_TIMER)		+= timer-mediatek.o
+obj-$(CONFIG_MTK_CPUX_TIMER)	+= timer-mediatek-cpux.o
+obj-$(CONFIG_CLKSRC_PISTACHIO)	+= timer-pistachio.o
+obj-$(CONFIG_CLKSRC_TI_32K)	+= timer-ti-32k.o
+obj-$(CONFIG_OWL_TIMER)		+= timer-owl.o
+obj-$(CONFIG_MILBEAUT_TIMER)	+= timer-milbeaut.o
+obj-$(CONFIG_SPRD_TIMER)	+= timer-sprd.o
+obj-$(CONFIG_NPCM7XX_TIMER)	+= timer-npcm7xx.o
+obj-$(CONFIG_RDA_TIMER)		+= timer-rda.o
+obj-$(CONFIG_REALTEK_OTTO_TIMER)	+= timer-rtl-otto.o
+
+obj-$(CONFIG_ARC_TIMERS)		+= arc_timer.o
+obj-$(CONFIG_ARM_ARCH_TIMER)		+= arm_arch_timer.o
+obj-$(CONFIG_ARM_ARCH_TIMER)		+= arm_arch_timer_mmio.o
+obj-$(CONFIG_ARM_GLOBAL_TIMER)		+= arm_global_timer.o
+obj-$(CONFIG_ARMV7M_SYSTICK)		+= armv7m_systick.o
+obj-$(CONFIG_ARM_TIMER_SP804)		+= timer-sp804.o
+obj-$(CONFIG_ARCH_HAS_TICK_BROADCAST)	+= dummy_timer.o
+obj-$(CONFIG_KEYSTONE_TIMER)		+= timer-keystone.o
+obj-$(CONFIG_INTEGRATOR_AP_TIMER)	+= timer-integrator-ap.o
+obj-$(CONFIG_CLKSRC_VERSATILE)		+= timer-versatile.o
+obj-$(CONFIG_CLKSRC_MIPS_GIC)		+= mips-gic-timer.o
+obj-$(CONFIG_CLKSRC_IMX_GPT)		+= timer-imx-gpt.o
+obj-$(CONFIG_CLKSRC_IMX_TPM)		+= timer-imx-tpm.o
+obj-$(CONFIG_TIMER_IMX_SYS_CTR)		+= timer-imx-sysctr.o
+obj-$(CONFIG_ASM9260_TIMER)		+= asm9260_timer.o
+obj-$(CONFIG_INGENIC_OST)		+= ingenic-ost.o
+obj-$(CONFIG_INGENIC_SYSOST)	+= ingenic-sysost.o
+obj-$(CONFIG_INGENIC_TIMER)		+= ingenic-timer.o
+obj-$(CONFIG_CLKSRC_ST_LPC)		+= clksrc_st_lpc.o
+obj-$(CONFIG_X86_NUMACHIP)		+= numachip.o
+obj-$(CONFIG_RISCV_TIMER)		+= timer-riscv.o
+obj-$(CONFIG_CLINT_TIMER)		+= timer-clint.o
+obj-$(CONFIG_CSKY_MP_TIMER)		+= timer-mp-csky.o
+obj-$(CONFIG_GX6605S_TIMER)		+= timer-gx6605s.o
+obj-$(CONFIG_HYPERV_TIMER)		+= hyperv_timer.o
+obj-$(CONFIG_MICROCHIP_PIT64B)		+= timer-microchip-pit64b.o
+obj-$(CONFIG_MSC313E_TIMER)		+= timer-msc313e.o
+obj-$(CONFIG_GOLDFISH_TIMER)		+= timer-goldfish.o
+obj-$(CONFIG_GXP_TIMER)			+= timer-gxp.o
+obj-$(CONFIG_CLKSRC_LOONGSON1_PWM)	+= timer-loongson1-pwm.o
+obj-$(CONFIG_EP93XX_TIMER)		+= timer-ep93xx.o
+obj-$(CONFIG_RALINK_TIMER)		+= timer-ralink.o
+obj-$(CONFIG_NXP_STM_TIMER)		+= timer-nxp-stm.o
+obj-$(CONFIG_RTK_SYSTIMER)		+= timer-realtek.o